Method and device for generating and mapping channel state information reference signal sequence

ABSTRACT

The present invention provides a method and device for generating and mapping a Channel State Information Reference Signal (CSI-RS) sequence, and the method includes: generating a pseudo-random sequence according to a pseudo-random sequence initial value, performing a Quadrature Phase-Shift Keying (QPSK) modulation on the pseudo-random sequence, and obtaining a first CSI-RS sequence according to maximum bandwidth of system; and cutting the first CSI-RS sequence according to the actual bandwidth of the system, obtaining a second CSI-RS sequence, and mapping the second CSI-RS sequence to a time frequency location of a CSI-RS antenna port. The CSI-RS reference signal sequence can be generated or obtained respectively at the UE terminal and eNB terminal in accordance with the stated methods for generating and mapping the reference sequence according to known parameters by the present invention, so that the calculated CSI-RS sequence can be utilized to measure the channel at the UE terminal.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application is a continuation application of U.S. patent Ser. No.13/501,470, filed on Apr. 12, 2012, and entitled “Method and Device forGenerating and Mapping Channel State Information Reference SignalSequence”, the disclosure of which is incorporated herein by referencein its entirety for all purposes.

TECHNICAL FIELD

The present invention relates to a Long term evolution advanced (LTE-A)system, and more especially, to a method and device for generating andmapping a Channel State Information Reference Signal (CSI-RS) sequencein the LTE-A system.

BACKGROUND OF THE RELATED ART

In the Long term evolution (LTE) Release 10 (R10), to further improvethe average frequency spectrum utilization rate and border frequencyspectrum utilization rate of a cell and the throughput rate of each UserEquipment (UE), two reference signals (also called the pilot) arerespectively defined: a Channel State Information Reference Signal(CRI-RS) and a Demodulation Reference Signal (DMRS), wherein the CRI-RSis used for measuring a channel, and a Precoding Matrix Indicator (PMI),Channel Quality Indicator (CQI) and Rank Indicator (RI) which arerequired to be fed back by the UE to an evolved Node B (eNB) can becalculated through measuring the CRI-RS. The distribution of the CSI-RSin time domain and frequency domain which was formerly defined by the3GPP LTE-A RAN1 61 bis conference is sparse, and it shall guarantee thatonly pilot density of one CSI-RS on each antenna port in a serving cellis included within a Resource Block (RB), and the multiple of 5 ms istaken as a period of the CSI-RS in time domain. During the 3GPP LTE-ARAN1 61 bis conference, the patterns under Normal Cyclic Prefix (NormalCP) and Extended Cyclic Prefix (Extended CP) were respectively definedfor Frequency Division Duplexing (FDD) system and Time DivisionDuplexing (TDD) system (refer to FIG. 1˜FIG. 8), wherein one CSI-RSantenna port multiplexes with another CSI-RS antenna port by means ofCode Division Multiple (CDM), two Orthogonal Frequency DivisionMultiplexing (OFDM) symbols are occupied in the time domain, andResource Element (RE) of one CSI-RS antenna port is included in one RBin the frequency domain.

However, the existing technology doesn't relate to how to generate andmap the CSI-RS sequence.

SUMMARY OF THE INVENTION

The purpose of the present invention is to provide a method and devicefor generating and mapping a channel state information reference signalsequence, to meet the requirements for the application of the ChannelState Information Reference Signal in the LTE-A technique.

In order to solve the above problems, the present invention provides amethod for generating and mapping the Channel State InformationReference Signal (CSI-RS) sequence, which comprises:

generating a pseudo-random sequence according to a pseudo-randomsequence initial value, performing a Quadrature Phase-Shift Keying(QPSK) modulation on the pseudo-random sequence, and obtaining a firstCSI-RS sequence according to maximum bandwidth of system; and

cutting the first CSI-RS sequence according to actual bandwidth of thesystem, obtaining a second CSI-RS sequence, and mapping the secondCSI-RS sequence to a time frequency location of a CSI-RS antenna port.

The method can generate the first CSI-RS sequence, cut the first CSI-RSsequence to obtain the second CSI-RS sequence and map the second CSI-RSsequence based on an Orthogonal Frequency Division Multiplexing (OFDM)symbol or a subframe; wherein

when the second CSI-RS sequence is mapped based on the OFDM symbol, thesecond CSI-RS sequences mapped on two OFDM symbols which are located inthe same Code Division Multiple (CDM) group are produced from differentfirst CSI-RS sequences;

when the second CSI-RS sequence is mapped based on the subframe, thesecond CSI-RS sequences mapped on the two OFDM symbols which are locatedin the same CDM group are produced from different parts of same firstCSI-RS sequence.

The method can generate the first CSI-RS sequence, cut the first CSI-RSsequence to obtain the second CSI-RS sequence and map the second CSI-RSsequence based on the OFDM symbol; and the method can further comprises:obtaining the pseudo-random sequence initial value according to a timeslot index, an OFDM symbol index in one time slot and a cell identity(ID), or

obtaining the pseudo-random sequence initial value according to one ormore of three parameters of a CSI-RS antenna port number relatedparameter, a CSI-RS antenna port index related parameter and a CyclicPrefix (CP) length factor, and the time slot index, the OFDM symbolindex in one time slot and the cell ID.

The pseudo-random sequence initial value c_(init) can be one of thefollowing values:c _(init)=2⁹·(7·(n _(s)+1)+l+1)·(2·N _(ID) ^(cell)+1)+N _(ID) ^(cell);c _(init)=2⁹·(7·(n _(s)+1)+l+1)·(2·N _(ID) ^(cell)+1);c _(init)=(7·(n _(s)+1)+l+1)·(2·N _(ID) ^(cell)+1);c _(init)=2¹⁰·(7·(n _(s)+1)+l+1)·(2·N _(ID) ^(cell)+1)+2·+N _(ID)^(cell) N _(CP);c _(init)=2¹⁰·(7·(n _(s)+1)+l+1)·(2·N _(ID) ^(cell)+1)+N _(CP);c _(init)=2·(7·(n _(s)+1)+l+1)·(2·N _(ID) ^(cell)+1)+N _(CP);c _(init)=2⁹·(7·(n _(s)+1)+l+1)·(2·N _(ID)^(cell)+1)·(2·└ANTPORT/4┘+1)+N _(ID) ^(cell);c _(init)=2⁹·(7·(n _(s)+1)+l+1)·(2·N _(ID)^(cell)+1)·(2·└ANTPORT/2┘+1)+N _(ID) ^(cell);c _(init)=(7·(n _(s)+1)+l+1)·(2·N _(ID) ^(cell)+1)·(2·└ANTPORT/4┘+1);c _(init)=(7·(n _(s)+1)+l+1)·(2·N _(ID) ^(cell)+1)·(2·└ANTPORT/2┘+1);c _(init)=4·(7·(n _(s)+1)+l+1)·(2·N _(ID) ^(cell)+1)+└ANTPORT/2┘;c _(init)=2·(7·(n _(s)+1)+l+1)·(2·N _(ID) ^(cell)+1)+└ANTPORT/4┘;c _(init)=2⁹·(7·(n _(s)+1)+l+1)·(2·N _(ID) ^(cell)+1)+└ANTPORT/2┘;c _(init)=2⁹·(7·(n _(s)+1)+l+1)·(2·N _(ID) ^(cell)+1)+└ANTPORT/4┘;c _(init)=2¹⁰·(7·(n _(s)+1)+l+1)·(2·N _(ID) ^(cell)+1)+└ANTPORT/2┘;c _(init)=2¹⁰·(7·(n _(s)+1)+l+1)·(2·N _(ID) ^(cell)+1)+└ANTPORT/4┘;c _(init)=2¹⁰·(7·(n _(s)+1)+l+1)·(2·N _(ID) ^(cell)+1)+└ANTPORT/2┘;c _(init)=2¹⁰·(7·(n _(s)+1)+l+1)·(2·N _(ID) ^(cell)+1)+2·N _(ID) ^(cell)+└ANTPORT/4┘;c _(init)=2¹¹·(7·(n _(s)+1)+l+1)·(2·N _(ID) ^(cell)+1)+4·N _(ID) ^(cell)+└ANTPORT/2┘;c _(init)=2¹⁰·(7·(n _(s)+1)+l+1)·(2·N _(ID)^(cell)+1)·(2·└ANTPORT/4┘+1)+2N _(ID) ^(cell) +N _(CP);c _(init)=2¹⁰·(7·(n _(s)+1)+l+1)·(2·N _(ID)^(cell)+1)·(2·└ANTPORT/2┘+1)+2N _(ID) ^(cell) +N _(CP);c _(init)=2·(7·(n _(s)+1)+l+1)·(2·N _(ID)^(cell)+1)·(2·└ANTPORT/4┘+1)+1)+N _(CP);c _(init)=8·(7·(n _(s)+1)+l+1)·(2·N _(ID) ^(cell)+1)+2·└ANTPORT/2┘+N_(CP);c _(init)=4·(7·(n _(s)+1)+l+1)·(2·N _(ID) ^(cell)+1)+2·└ANTPORT/4┘+N_(CP);c _(init)=2⁹·(7·(n _(s)+1)+l+1)·(2·N _(ID) ^(cell)+1)+2·└ANTPORT/2┘+N_(CP);c _(init)=2⁹·(7·(n _(s)+1)+l+1)·(2·N _(ID) ^(cell)+1)+2·└ANTPORT/4┘+N_(CP);c _(init)=2¹⁰·(7·(n _(s)+1)+l+1)·(2·N _(ID) ^(cell)+1)+2·└ANTPORT/4┘+N_(CP);c _(init)=2¹⁰·(7·(n _(s)+1)+l+1)·(2·N _(ID) ^(cell)+1)+2·└ANTPORT/2┘+N_(CP);c _(init)=2⁹·(7·(n _(s)+1)+l+1)·(2·N _(ID) ^(cell)+1)·2·ANTPORTNUM+1)+N_(ID) ^(cell);c _(init)=2⁹·(7·(n _(s)+1)+l+1)·(2·N _(ID) ^(cell)+1)·2·ANTPORTNUM+1);c _(init)=2¹¹·(7·(n _(s)+1)+l+1)·(2·N _(ID) ^(cell)+1)+4N _(ID) ^(cell)+ANTPORTNUM;c _(init)=2⁹·(7·(n _(s)+1)+l+1)·(2·N _(ID) ^(cell)+1)+ANTPORTNUM;c _(init)=4·(7·(n _(s)+1)+l+1)·(2·N _(ID) ^(cell)+1)+ANTPORTNUM;c _(init)=2⁹·(7·(n _(s)+1)+l+1)·(2·N _(ID) ^(cell)+1)·(2·ANTPORTNUM+1)+N_(ID) ^(cell);c _(init)=2¹¹·(7·(n _(s)+1)+l+1)·(2·N _(ID) ^(cell)+1)+4N _(ID) ^(cell)+ANTPORTNUM;c _(init)=2¹²·(7·(n _(s)+1)+l+1)·(2·N _(ID) ^(cell)+1)+8N _(ID)^(cell)+4N _(CP) +ANTPORTNUM;c _(init)=2⁹·(7·(n _(s)+1)+l+1)·(2·N _(ID) ^(cell)+1)+4N _(CP)+ANTPORTNUM;c _(init)=8·(7·(n _(s)+1)+l+1)·(2·N _(ID) ^(cell)+1)+4N _(CP)+ANTPORTNUM;c _(init)=2¹²·(7·(n _(s)+1)+l+1)·(2·N _(ID) ^(cell)+1)+8N _(ID)^(cell)+2ANTPORTNUM+N _(CP);c _(init)=2⁹·(7·(n _(s)+1)+l+1)·(2·N _(ID) ^(cell)+1)+2ANTPORTNUM+N_(CP);c _(init)=8·(7·(n _(s)+1)+l+1)·(2·N _(ID) ^(cell)+1)+2ANTPORTNUM+N_(CP);c _(init)=2¹¹·(7·(n _(s)+1)+l+1)·(2·N _(ID)^(cell)+1)(2·└ANTPORT/4┘+1)+4N _(ID) ^(cell) +ANTPORTNUM;c _(init)=2⁹·(7·(n _(s)+1)+l+1)·(2·N _(ID)^(cell)+1)(2·└ANTPORT/4┘+1)+ANTPORTNUM;c _(init)=4·(7·(n _(s)+1)+l+1)·(2·N _(ID)^(cell)+1)(2·└ANTPORT/4┘+1)+ANTPORTNUM;c _(init)=2¹⁰·(7·(n _(s)+1)+l+1)·(2·N _(ID)^(cell)+1)+8·└ANTPORT/4┘+ANTPORTNUM;c _(init)=2¹⁰·(7·(n _(s)+1)+l+1)·(2·N _(ID)^(cell)+1)+8·└ANTPORT/2┘+ANTPORTNUM;c _(init)=2⁹·(7·(n _(s)+1)+l+1)·(2·N _(ID)^(cell)+1)(2·└ANTPORT/4┘+1)+8N _(ID) ^(cell)+4N _(CP) +ANTPORTNUM;c _(init)=2⁹·(7·(n _(s)+1)+l+1)·(2·N _(ID)^(cell)+1)(2·└ANTPORT/4┘+1)+4N _(CP) +ANTPORTNUM;c _(init)=2¹²·(7·(n _(s)+1)+l+1)·(2·N _(ID)^(cell)+1)(2·└ANTPORT/4┘+1)+8N _(ID) ^(cell)+2ANTPORTNUM+N _(CP);c _(init)=2⁹·(7·(n _(s)+1)+l+1)·(2·N _(ID)^(cell)+1)(2·└ANTPORT/4┘+1)+1)+2ANTPORTNUM+N _(CP);c _(init)=8·(7·(n _(s)+1)+l+1)·(2·N _(ID)^(cell)+1)(2·└ANTPORT/4┘+1)+1)+2ANTPORTNUM+N _(CP);c _(init)=2¹⁰·(7·(n _(s)+1)+l+1)·(2·N _(ID)^(cell)+1)+8·└ANTPORT/2┘+ANTPORTNUM+N _(CP);

wherein, n_(s) is the time slot index in one radio frame, l is the OFDMindex in one time slot, N_(ID) ^(cell) is the cell ID, and N_(CP) is theCyclic Prefix (CP) length factor. When a subframe is a normal CPsubframe, N_(CP)=1, and when the subframe is an extended CP subframe,N_(CP)=0, ANTPORT is the CSI-RS antenna port index related parameter,and ANTPORTNUM is the CSI-RS antenna port number related parameter ofcell.

The method can generate the first CSI-RS sequence, cut the first CSI-RSsequence to obtain the second CSI-RS sequence and map the second CSI-RSsequence based on the subframe, and the method can further comprise:

obtaining the pseudo-random sequence initial value according to the timeslot index and cell ID; or

obtaining the pseudo-random sequence initial value according to one ormore of three parameters of the CSI-RS antenna port number relatedparameter, the CSI-RS antenna port index related parameter and theCyclic Prefix (CP) length factor, and the time slot index and the cellID.

The pseudo-random sequence initial value c_(init) can be one of thefollowing values:c _(init)=(└n _(s)/2┘+1)·(2N _(ID) ^(cell)+1)·2¹⁶;c _(init)=(└n _(s)/2┘+1)·(2N _(ID) ^(cell)+1);c _(init)=(└n _(s)/2┘+1)·(2N _(ID) ^(cell)+1)·2¹⁶ +N _(ID) ^(cell);c _(init)=(└n _(s)/2┘+1)·(2N _(ID) ^(cell)+1)·2⁹ +N _(ID) ^(cell);c _(init)=(└n _(s)/2┘+1)·(2N _(ID) ^(cell)+1)·2¹⁶ +N _(ID) ^(cell) +N^(CP);c _(init)=(└n _(s)/2┘+1)·(2N _(ID) ^(cell)+1)·2¹⁶ +N _(CP);c _(init)=(└n _(s)/2┘+1)·(2N _(ID) ^(cell)+1)·2¹⁰+2N _(ID)^(cell)+_(CP);c _(init)=(└n _(s)/2┘+1)·(2N _(ID) ^(cell)+1)·(2·└ANTPORT/2┘+1)·2⁹ +N_(ID) ^(cell);c _(init)=(└n _(s)/2┘+1)·(2N _(ID) ^(cell)+1)·(2·└ANTPORT/4┘+1)·2⁹ +N_(ID) ^(cell);c _(init)=(└n _(s)/2┘+1)·(2N _(ID) ^(cell)+1)·(2·└ANTPORT/2┘+1);c _(init)=(└n _(s)/2┘+1)·(2N _(ID) ^(cell)+1)·2¹⁶ +└ANTPORT/2┘;c _(init)=(└n _(s)/2┘+1)·(2N _(ID) ^(cell)+1)·2¹⁶ +└ANTPORT/4┘;c _(init)=(└n _(s)/2┘+1)·(2N _(ID) ^(cell)+1)·(2·└ANTPORT/2┘+1)·2¹⁰+2N_(ID) ^(cell) +N _(CP);c _(init)=(└n _(s)/2┘+1)·(2N _(ID) ^(cell)+1)·(2·└ANTPORT/4┘+1)·2¹⁰+2N_(ID) ^(cell) +N _(CP);c _(init)=(└n _(s)/2┘+1)·(2N _(ID) ^(cell)+1)·(2·└ANTPORT/4┘+1)·2+N_(CP);c _(init)=2¹⁶·(└n _(s)/2┘+1)·(2N _(ID) ^(cell)+1)·2·└ANTPORT/4┘+N _(CP);c _(init)=2¹⁶·(└n _(s)/2┘+1)·(2N _(ID) ^(cell)+1)·2·└ANTPORT/2┘+N _(CP);c _(init)=(└n _(s)/2┘+1)·(2N _(ID) ^(cell)+1)·(2·ANTPORTNUM+1)·2¹⁰+2N_(ID) ^(cell) +N _(CP);c _(init)=(└n _(s)/2┘+1)·(2N _(ID) ^(cell)+1)·2¹²+8N _(ID) ^(cell)+4N_(CP) +ANTPORTNUM;c _(init)=(└n _(s)/2┘+1)·(2N _(ID) ^(cell)+1)·2¹²+8N _(ID)^(cell)+2ANTPORTNUM+N _(CP);c _(init)=(└n _(s)/2┘+1)·(2N _(ID) ^(cell)+1)·2³+2ANTPORTNUM+N _(CP);c _(init)=(└n _(s)/2┘+1)·(2N _(ID) ^(cell)+1)·2³4N _(CP) +ANTPORTNUM;c _(init)=(└n _(s)/2┘+1)·(2N _(ID) ^(cell)+1)·(2·ANTPORTNUM+1)·2⁹ +N_(ID) ^(cell);c _(init)=(└n _(s)/2┘+1)·(2N _(ID) ^(cell)+1)·(2·ANTPORTNUM+1);c _(init)=(└n _(s)/2┘+1)·(2N _(ID) ^(cell)+1)·2¹⁶ +ANTPORTNUM;c _(init)=(└n _(s)/2┘+1)·(2N _(ID) ^(cell)+1)·4+ANTPORTNUM;c _(init)=(└n _(s)/2┘+1)·(2N _(ID) ^(cell)+1)·2¹¹+4N _(ID) ^(cell)+ANTPORTNUM;c _(init)=(└n _(s)/2┘+1)·(2N _(ID) ^(cell)+1)·(2·└ANTPORT/4┘+1)·2¹¹+4N_(ID) ^(cell) +ANTPORTNUM;c _(init)=(└n _(s)/2┘+1)·(2N _(ID)^(cell)+1)·(2·└ANTPORT/4┘+1)·4+ANTPORTNUM;c _(init)=(└n _(s)/2┘+1)·(2N _(ID) ^(cell)+1)·(2·└ANTPORT/4┘+1)·2¹⁶+ANTPORTNUM;c _(init)=(└n _(s)/2┘+1)·(2N _(ID)^(cell)+1)·2¹⁶+8·└ANTPORT/2┘++ANTPORTNUM;c _(init)=(└n _(s)/2┘+1)·(2N _(ID)^(cell)+1)·2¹⁶+8·└ANTPORT/4┘++ANTPORTNUM;c _(init)=(└n _(s)/2┘+1)·(2N _(ID) ^(cell)+1)·2¹⁶+2⁴·└ANTPORT/2┘+2·ANTPORTNUM+N _(CP);c _(init)=(└n _(s)/2┘+1)·(2N _(ID) ^(cell)+1)·2¹⁶+2⁴·└ANTPORT/4┘+2·ANTPORTNUM+N _(CP);

wherein, n_(s) is the time slot index in one radio frame, N_(ID) ^(cell)is the cell ID, when the subframe is the normal CP subframe, N_(CP)=1,and when the subframe is the extended CP subframe, N_(CP)=0, ANTPORT isthe CSI-RS antenna port index related parameter, and ANTPORTNUM is theCSI-RS antenna port number related parameter of the cell.

The method can generate the first CSI-RS sequence and cut the firstCSI-RS sequence to obtain the second CSI-RS sequence and map the secondCSI-RS sequence based on the OFDM symbol; wherein

in the step of generating the pseudo-random sequence according to thepseudo-random sequence initial value and performing the QPSK modulationon the pseudo-random sequence to obtain the first CSI-RS sequence,

the pseudo-random sequence c(n) can be generated in accordance with thefollowing ways:c(n)=(x ₁(n+N _(C))+x ₂(n+N _(C)))mod 2x ₁(n+31)=(x ₁(n+3)+x ₁(n))mod 2x ₂(n+31)=(x ₂(n+3)+x ₂(n+2)+x ₂(n+1)+x ₂(n))mod 2

wherein, x₁(0)=1, x₁(n)=0, n=1, 2, . . . , 30, N_(C)=1600,

x₂(n)=0, n=0, 1, 2, . . . , 30 are produced according to thepseudo-random sequence initial value c_(init)=Σ_(q=0) ³⁰x₂(q)·2^(q), andmod is a modular arithmetic; and

the first CSI-RS sequence r(m) can be generated in accordance with thefollowing ways:

${{r(m)} = {{\frac{1}{\sqrt{2}}( {1 - {2 \cdot {c( {2\; m} )}}} )} + {j\frac{1}{\sqrt{2}}( {1 - {{2 \cdot c}( {{2\; m} + 1} )}} )}}},{m = 0},1,\ldots\mspace{14mu},{N_{RB}^{\max,{DL}} - 1}$or${{r(m)} = {{\frac{1}{\sqrt{2}}( {1 - {2 \cdot {c( {2\; m} )}}} )} + {j\frac{1}{\sqrt{2}}( {1 - {{2 \cdot c}( {{2\; m} + 1} )}} )}}},{m = \lceil {\frac{1}{2}N_{RB}^{\max,{DL}}} \rceil},\ldots\mspace{14mu},{\lceil {\frac{3}{2}N_{RB}^{\max,{DL}}} \rceil - 1}$

wherein, N_(RB) ^(max,DL) is the maximum bandwidth of the system, N_(RB)^(max,DL)=110.

The step of cutting the first CSI-RS sequence according to the actualbandwidth of the system can comprise: calculating a location index i′according to the actual bandwidth N_(RB) ^(DL) of the system and cuttingthe first CSI-RS sequence r(m) in accordance with the location index i′to obtain the second CSI-RS sequence r_(l,n) _(s) (i′) of the OFDMsymbol l on the time slot n_(s); and the step of mapping the secondCSI-RS sequence to the time frequency location of the CSI-RS antennaport can comprise: mapping the second CSI-RS sequence r_(l,n) _(s) (i′)to a subcarrier k of the OFDM symbol l of CSI-RS antenna port p viaa_(k,l) ^((p))=w_(l″)·r_(l,n) _(s) (i′), wherein, a_(k,l) ^((p)) is avalue of RE corresponding to the CSI-RS antenna port p, and w_(l″) is anorthogonal code factor.

The location index can be

${i^{\prime} = {i + \frac{\lfloor {N_{RB}^{\max,{DL}} - N_{RB}^{DL}} \rfloor}{2}}},{i = 0},{1\ldots}\mspace{14mu},{{N_{RB}^{DL} - 1};}$

in the step of mapping the second CSI-RS sequence r_(l,n) _(s) (i′) tothe subcarrier k of the OFDM symbol l of the CSI-RS antenna port p,a_(k,l) ^((p))=w_(l″)·r_(l,n) _(s) (i′), there is:

$\mspace{20mu}{k = {k^{\prime} + {12\; i} + \{ {{\begin{matrix}{- 0} & {{p \in \{ {15,16} \}},{{normal}\mspace{14mu}{CP}}} \\{- 6} & {{p \in \{ {17,18} \}},{{normal}\mspace{14mu}{CP}}} \\{- 1} & {{p \in \{ {19,20} \}},{{normal}\mspace{14mu}{CP}}} \\{- 7} & {{p \in \{ {21,22} \}},{{normal}\mspace{14mu}{CP}}} \\{- 0} & {{p \in \{ {15,16} \}},{{extended}\mspace{14mu}{CP}}} \\{- 3} & {{p \in \{ {17,18} \}},{{extended}\mspace{14mu}{CP}}} \\{- 6} & {{p \in \{ {19,20} \}},{{extended}\mspace{14mu}{CP}}} \\{- 9} & {{p \in \{ {21,22} \}},{{extended}\mspace{14mu}{CP}}}\end{matrix}l} = \{ {\begin{matrix}l^{\prime} & \begin{matrix}{{when}\mspace{14mu}{using}\mspace{14mu}{the}\mspace{14mu}{extended}\mspace{14mu}{CP}{\mspace{11mu}\;}{and}\mspace{14mu}{the}\mspace{14mu}{subframe}\mspace{14mu}{structure}} \\{{{type}\mspace{14mu} 1\mspace{14mu}{or}\mspace{14mu} 2},{{the}\mspace{14mu}{first}\mspace{14mu}{symbol}\mspace{14mu}{of}\mspace{14mu}{the}\mspace{14mu}{CDM}\mspace{14mu}{group}}}\end{matrix} \\{l^{\prime} + 1} & \begin{matrix}{{when}\mspace{14mu}{using}\mspace{14mu}{the}\mspace{14mu}{extended}\mspace{14mu}{CP}{\mspace{11mu}\;}{and}\mspace{14mu}{the}\mspace{14mu}{subframe}\mspace{14mu}{structure}} \\{{{type}\mspace{14mu} 1\mspace{14mu}{or}\mspace{14mu} 2},{{the}\mspace{14mu}{second}\mspace{14mu}{symbol}\mspace{14mu}{of}\mspace{14mu}{the}\mspace{14mu}{CDM}\mspace{14mu}{group}}}\end{matrix} \\{l^{\prime} + 2} & \begin{matrix}{{when}\mspace{14mu}{using}\mspace{14mu}{the}\mspace{14mu}{normal}\mspace{14mu}{CP}{\mspace{11mu}\;}{and}\mspace{14mu}{the}\mspace{14mu}{subframe}\mspace{14mu}{structure}} \\{{{type}\mspace{14mu} 2},{{the}\mspace{14mu}{second}\mspace{14mu}{symbol}\mspace{14mu}{of}\mspace{14mu}{the}\mspace{14mu}{CDM}\mspace{14mu}{group}}}\end{matrix}\end{matrix}\mspace{20mu} l^{''}\{ {{\begin{matrix}{0,{l = l^{\prime}}} \\{1,{l \neq l^{\prime}},}\end{matrix}\mspace{14mu} w_{l^{\prime}}} = \{ \begin{matrix}1 & {p \in \{ {15,17,19,21} \}} \\( {- 1} )^{l^{''}} & {{p \in \{ {16,18,20,22} \}};}\end{matrix} } } } }}$

wherein, k′ is a frequency domain location of first CSI-RS antenna port,l′ is an initial time domain location of first CSI-RS antenna port, andthe first CSI-RS sequence r(m) is

${{r(m)} = {{\frac{1}{\sqrt{2}}( {1 - {2 \cdot {c( {2\; m} )}}} )} + {j\frac{1}{\sqrt{2}}( {1 - {{2 \cdot c}( {{2\; m} + 1} )}} )}}},{m = 0},1,\ldots\mspace{14mu},{N_{RB}^{\max,{DL}} - 1.}$

The location index can be

${i^{\prime} = {i + \frac{\lfloor {N_{RB}^{\max,{DL}} - N_{RB}^{DL}} \rfloor}{2}}},$i=0, 1, . . . , N_(RB) ^(DL)−1;

in the step of mapping the second CSI-RS sequence r_(l,n) _(s) (i′) tothe subcarrier k of the

OFDM  symbol  l  of  the  CSI-RS  antenna  port  p, a_(k, l)^((p)) = w_(l^(″)) ⋅ r_(l, n_(z))(i^(′)), there  is:$k = {k^{\prime} + {12\; i} + \{ {{\begin{matrix}{- 0} & {{p \in \{ {15,16} \}},{{normal}\mspace{14mu}{CP}}} \\{- 6} & {{p \in \{ {17,18} \}},{{normal}\mspace{14mu}{CP}}} \\{- 1} & {{p \in \{ {19,20} \}},{{normal}\mspace{14mu}{CP}}} \\{- 7} & {{p \in \{ {21,22} \}},{{normal}\mspace{14mu}{CP}}} \\{- 0} & {{p \in \{ {15,16} \}},{{extended}\mspace{14mu}{CP}}} \\{- 3} & {{p \in \{ {17,18} \}},{{extended}\mspace{14mu}{CP}}} \\{- 6} & {{p \in \{ {19,20} \}},{{extended}\mspace{14mu}{CP}}} \\{- 9} & {{p \in \{ {21,22} \}},{{extended}\mspace{14mu}{CP}}}\end{matrix}l} = {l^{\prime} + \{ {{{\begin{matrix}l^{''} & \begin{matrix}{{{when}\mspace{14mu}{using}\mspace{14mu}{normal}{\mspace{11mu}\;}{CP}},} \\{{{CSI}\text{-}{RS}\mspace{14mu}{configuration}\mspace{14mu}{index}\mspace{14mu}{is}\mspace{14mu} 0} \sim 19}\end{matrix} \\{2\; l^{''}} & \begin{matrix}{{{when}\mspace{14mu}{using}\mspace{14mu}{normal}{\mspace{11mu}\;}{CP}},} \\{{{CSI}\text{-}{RS}\mspace{14mu}{configuration}\mspace{14mu}{index}\mspace{14mu}{is}\mspace{14mu} 20} \sim 31}\end{matrix} \\l^{''} & \begin{matrix}{{{when}\mspace{14mu}{using}\mspace{14mu}{extended}{\mspace{11mu}\;}{CP}},} \\{{{CSI}\text{-}{RS}\mspace{14mu}{configuration}\mspace{14mu}{index}\mspace{14mu}{is}\mspace{14mu} 0} \sim 27}\end{matrix}\end{matrix}l^{''}} \in \{ {0,1} \}},\mspace{14mu}{w_{l^{\prime}} = \{ \begin{matrix}1 & {p \in \{ {15,17,19,21} \}} \\( {- 1} )^{l^{''}} & {{p \in \{ {16,18,20,22} \}},}\end{matrix} }} }} }$

wherein, k′ is the frequency domain location of the first CSI-RS antennaport, l′ is the initial time domain location of the first CSI-RS antennaport, and the first CSI-RS sequence r(m) is

${{r(m)} = {{\frac{1}{\sqrt{2}}( {1 - {2 \cdot {c( {2\; m} )}}} )} + {j\frac{1}{\sqrt{2}}( {1 - {{2 \cdot c}( {{2\; m} + 1} )}} )}}},{m = 0},1,\ldots\mspace{14mu},{N_{RB}^{\max,{DL}} - 1.}$

The location index can be

$i^{\prime} = \{ {{{\begin{matrix}{i + \lfloor \frac{N_{RB}^{\max,{DL}} - N_{RB}^{DL}}{2} \rfloor} & {l^{''} = 0} \\{i - N_{RB}^{DL} + \lfloor \frac{N_{RB}^{\max,{DL}} - N_{RB}^{DL}}{2} \rfloor} & {{l^{''} = 1},}\end{matrix}i} = 0},1,\ldots\mspace{14mu},{{2\; N_{RB}^{DL}} - 1},} $and the first CSI-RS sequence r(m) is cut to obtain the second CSI-RSsequence r_(l,n) _(s) (i′) on the time slot n_(s) of the OFDM symbol l;

in the step of mapping the second CSI-RS sequence r_(l,n) _(s) (i′) tothe subcarrier k of the OFDM symbol l of the CSI-RS antenna port p,a_(k,l) ^((p))=w_(l″)·r_(l,n) _(s) (i′), there is:

$k = {k^{\prime} + {12( {i\;{mod}\; N_{RB}^{DL}} )} + \{ {{\begin{matrix}{- 0} & {{p \in \{ {15,16} \}},{{normal}\mspace{14mu}{CP}}} \\{- 6} & {{p \in \{ {17,18} \}},{{normal}\mspace{14mu}{CP}}} \\{- 1} & {{p \in \{ {19,20} \}},{{normal}\mspace{14mu}{CP}}} \\{- 7} & {{p \in \{ {21,22} \}},{{normal}\mspace{14mu}{CP}}} \\{- 0} & {{p \in \{ {15,16} \}},{{extended}\mspace{14mu}{CP}}} \\{- 3} & {{p \in \{ {17,18} \}},{{extended}\mspace{14mu}{CP}}} \\{- 6} & {{p \in \{ {19,20} \}},{{extended}\mspace{14mu}{CP}}} \\{- 9} & {{p \in \{ {21,22} \}},{{extended}\mspace{14mu}{CP}}}\end{matrix}l} = {l^{\prime} + \{ {{{\begin{matrix}l^{''} & \begin{matrix}{{{when}\mspace{14mu}{using}\mspace{14mu}{normal}{\mspace{11mu}\;}{CP}},} \\{{{CSI}\text{-}{RS}\mspace{14mu}{configuration}\mspace{14mu}{index}\mspace{14mu}{is}\mspace{14mu} 0} \sim 19}\end{matrix} \\{2\; l^{''}} & \begin{matrix}{{{when}\mspace{14mu}{using}\mspace{14mu}{normal}{\mspace{11mu}\;}{CP}},} \\{{{CSI}\text{-}{RS}\mspace{14mu}{configuration}\mspace{14mu}{index}\mspace{14mu}{is}\mspace{14mu} 20} \sim 31}\end{matrix} \\l^{''} & \begin{matrix}{{{when}\mspace{14mu}{using}\mspace{14mu}{extended}{\mspace{11mu}\;}{CP}},} \\{{{CSI}\text{-}{RS}\mspace{14mu}{configuration}\mspace{14mu}{index}\mspace{14mu}{is}\mspace{14mu} 0} \sim 27}\end{matrix}\end{matrix}l^{''}} = {\lfloor \frac{i}{N_{RB}^{DL}} \rfloor \in \{ {0,1} \}}},\mspace{14mu}{w_{l^{\prime}} = \{ \begin{matrix}1 & {p \in \{ {15,17,19,21} \}} \\( {- 1} )^{l^{''}} & {{p \in \{ {16,18,20,22} \}},}\end{matrix} }} }} }$

wherein, k′ is the frequency domain location of the first CSI-RS antennaport, l′ is the initial time domain location of the first CSI-RS antennaport, and the first CSI-RS sequence r(m) is

${{r(m)} = {{\frac{1}{\sqrt{2}}( {1 - {2 \cdot {c( {2m} )}}} )} + {j\frac{1}{\sqrt{2}}( {1 - {2 \cdot {c( {{2m} + 1} )}}} )}}},{m = 0},1,\ldots\;,{N_{RB}^{\max,{DL}} - 1.}$

The location index can be

${\mathbb{i}}^{\prime} = \{ {{{\begin{matrix}{{\mathbb{i}} + N_{RB}^{\max,{DL}} - \lfloor \frac{N_{RB}^{DL}}{2} \rfloor} & {l^{''} = 0} \\{{\mathbb{i}} - N_{RB}^{DL} + N_{RB}^{\max,{DL}} - \lfloor \frac{N_{RB}^{DL}}{2} \rfloor} & {{l^{''} = 1},}\end{matrix}{\mathbb{i}}} = 0},1,\ldots\;,{{{2N_{RB}^{DL}} - 1};}} $in the step of mapping the second CSI-RS sequence r_(l,n) _(s) (i′) tothe subcarrier k of the OFDM symbol l of the CSI-RS antenna port p,a_(k,l) ^((p)=w) _(l″)·r_(l,n) _(s) (i′), there is:

$\mspace{76mu}{k = {k^{\prime} + {12( {{\mathbb{i}}\;{mod}\; N_{RB}^{DL}} )} + \{ {{\begin{matrix}{- 0} & {{p \in \{ {15,16} \}},{{normal}\mspace{14mu}{CP}}} \\{- 6} & {{p \in \{ {17,18} \}},{{normal}\mspace{14mu}{CP}}} \\{- 1} & {{p \in \{ {19,20} \}},{{normal}\mspace{14mu}{CP}}} \\{- 7} & {{p \in \{ {21,22} \}},{{normal}\mspace{14mu}{CP}}} \\{- 0} & {{p \in \{ {15,16} \}},{{extended}\mspace{14mu}{CP}}} \\{- 3} & {{p \in \{ {17,18} \}},{{extended}\mspace{14mu}{CP}}} \\{- 6} & {{p \in \{ {19,20} \}},{{extended}\mspace{14mu}{CP}}} \\{- 9} & {{p \in \{ {21,22} \}},{{extended}\mspace{14mu}{CP}}}\end{matrix}l} = {l^{\prime} + \{ {{{\begin{matrix}l^{''} & {{{{when}\mspace{14mu}{using}\mspace{14mu}{normal}\mspace{14mu}{CP}},{{CSI}\text{-}{RS}\mspace{14mu}{configuration}\mspace{14mu}{index}\mspace{14mu}{is}\mspace{14mu}{ 0 \sim 19}}}\mspace{14mu}} \\{2l^{''}} & {{{when}\mspace{14mu}{using}\mspace{14mu}{normal}\mspace{14mu}{CP}},{{CSI}\text{-}{RS}\mspace{14mu}{configuration}\mspace{14mu}{index}\mspace{14mu}{is}\mspace{14mu}{ 20 \sim 31}}} \\l^{''} & {{{when}\mspace{14mu}{using}\mspace{14mu}{extended}\mspace{14mu}{CP}},{{CSI}\text{-}{RS}\mspace{14mu}{configuration}\mspace{14mu}{index}\mspace{14mu}{is}\mspace{14mu}{ 0 \sim 27}}}\end{matrix}\mspace{79mu} l^{''}} = {\lfloor {{\mathbb{i}}/N_{RB}^{DL}} \rfloor \in \{ {0,1} \}}},{w_{l^{''}} = \{ \begin{matrix}1 & {p \in \{ {15,17,19,21} \}} \\( {- 1} )^{l^{''}} & {{p \in \{ {16,18,20,22} \}},}\end{matrix} }} }} }}$

wherein, k′ is the frequency domain location of the first CSI-RS antennaport, l′ is the initial time domain location of the first CSI-RS antennaport, and the first CSI-RS sequence r(m) is

${{r(m)} = {{\frac{1}{\sqrt{2}}( {1 - {2 \cdot {c( {2m} )}}} )} + {j\frac{1}{\sqrt{2}}( {1 - {2 \cdot {c( {{2m} + 1} )}}} )}}},{m = \lceil {\frac{1}{2}N_{RB}^{\max,{DL}}} \rceil},\ldots\;,{\lceil {\frac{3}{2}N_{RB}^{\max,{DL}}} \rceil - 1.}$

The method can generate the first CSI-RS sequence, cut the first CSI-RSsequence to obtain the second CSI-RS sequence and map the second CSI-RSsequence based on the subframe; and in the step of obtaining thepseudo-random sequence according to the pseudo-random sequence initialvalue and performing the QPSK modulation on the pseudo-random sequenceto obtain the first CSI-RS sequence,

the pseudo-random sequence c(n) can be generated in accordance with thefollowing ways:c(n)=(x ₁(n+N _(C))+x ₂(n+N _(C)))mod 2x ₁(n+31)=(x ₁(n+3)+x ₁(n))mod 2x ₂(n+31)=(x ₂(n+3)+x ₂(n+2)+x ₂(n+1)+x ₂(n))mod 2

wherein, x₁(0)=1, x₁(n)=0, n=1, 2, . . . , 30, N_(C)=1600,

x₂(n)=0, n=0, 1, 2, . . . , 30 are produced according to thepseudo-random sequence initial value c_(init)=Σ_(q=0) ³⁰x₂(q)·2^(q), andmod is a modular arithmetic;

the first CSI-RS sequence r(m) can be generated in accordance with thefollowing ways:

${{r(m)} = {{\frac{1}{\sqrt{2}}( {1 - {2 \cdot {c( {2m} )}}} )} + {j\frac{1}{\sqrt{2}}( {1 - {2 \cdot {c( {{2m} + 1} )}}} )}}},{m = 0},1,\ldots\;,{{{2N_{RB}^{\max,{DL}}} - 1};}$

wherein, N_(RB) ^(max,DL) is the maximum system bandwidth, N_(RB)^(max,DL)=110.

The step of cutting the first CSI-RS sequence according to the actualbandwidth of the system can comprise: calculating a location index i′according to the actual bandwidth of the system and cutting the firstCSI-RS sequence r(m) according to the location index i′ to obtain thesecond CSI-RS sequence r_(n) _(s) (i′) on the subframe

$\lfloor \frac{n_{s}}{2} \rfloor;$and the step of mapping the second CSI-RS sequence to the time frequencylocation of the CSI-RS antenna port can comprise: mapping the secondCSI-RS sequence r_(n) _(s) (i′) to the subcarrier k of the OFDM symbol lof the CSI-RS antenna port p via a_(k,l) ^((p)=w) _(l″)·r_(n) _(s) (i′);

wherein, a_(k,l) ^((p)) is the value of RE corresponding to the CSI-RSantenna port p, w_(l″) is the orthogonal code factor, and n_(s) is thetime slot index.

The location index can be i′=i+N_(RB) ^(max,DL)−N_(RB) ^(DL), i=0, 1, .. . , 2N_(RB) ^(DL)−1;

in the step of mapping the second CSI-RS sequence r_(n) _(s) (i′) to thesubcarrier k of the OFDM symbol l of the CSI-RS antenna port p, thereis:

$\mspace{76mu}{k = {k^{\prime} + {12( {{\mathbb{i}}\;{mod}\; N_{RB}^{DL}} )} + \{ {{\begin{matrix}{- 0} & {{p \in \{ {15,16} \}},{{normal}\mspace{14mu}{CP}}} \\{- 6} & {{p \in \{ {17,18} \}},{{normal}\mspace{14mu}{CP}}} \\{- 1} & {{p \in \{ {19,20} \}},{{normal}\mspace{14mu}{CP}}} \\{- 7} & {{p \in \{ {21,22} \}},{{normal}\mspace{14mu}{CP}}} \\{- 0} & {{p \in \{ {15,16} \}},{{extended}\mspace{14mu}{CP}}} \\{- 3} & {{p \in \{ {17,18} \}},{{extended}\mspace{14mu}{CP}}} \\{- 6} & {{p \in \{ {19,20} \}},{{extended}\mspace{14mu}{CP}}} \\{- 9} & {{p \in \{ {21,22} \}},{{extended}\mspace{14mu}{CP}}}\end{matrix}l} = {l^{\prime} + \{ {{{\begin{matrix}l^{''} & {{{{when}\mspace{14mu}{using}\mspace{14mu}{normal}\mspace{14mu}{CP}},{{CSI}\text{-}{RS}\mspace{14mu}{configuration}\mspace{14mu}{index}\mspace{14mu}{is}\mspace{14mu}{ 0 \sim 19}}}\mspace{14mu}} \\{2l^{''}} & {{{when}\mspace{14mu}{using}\mspace{14mu}{normal}\mspace{14mu}{CP}},{{CSI}\text{-}{RS}\mspace{14mu}{configuration}\mspace{14mu}{index}\mspace{14mu}{is}\mspace{14mu}{ 20 \sim 31}}} \\l^{''} & {{{when}\mspace{14mu}{using}\mspace{14mu}{extended}\mspace{14mu}{CP}},{{CSI}\text{-}{RS}\mspace{14mu}{configuration}\mspace{14mu}{index}\mspace{14mu}{is}\mspace{14mu}{ 0 \sim 27}}}\end{matrix}\mspace{79mu} l^{''}} = {\lfloor {{\mathbb{i}}/N_{RB}^{DL}} \rfloor \in \{ {0,1} \}}},{w_{l^{''}} = \{ \begin{matrix}1 & {p \in \{ {15,17,19,21} \}} \\( {- 1} )^{l^{''}} & {{p \in \{ {16,18,20,22} \}},}\end{matrix} }} }} }}$

wherein, k′ is the frequency domain location of the first CSI-RS antennaport, and l′ is the initial time domain location of the first CSI-RSantenna port.

In order to solve the above problems, the present invention furtherprovides a device for generating and mapping CSI-RS sequence, comprisinga generating unit and a mapping unit, wherein:

the generating unit is configured to: generate a pseudo-random sequenceaccording to a pseudo-random sequence initial value, perform a QPSKmodulation on the pseudo-random sequence, and obtain a first CSI-RSsequence according to maximum bandwidth of system;

the mapping unit is configured to: cut the first CSI-RS sequenceaccording to actual bandwidth of the system, obtain a second CSI-RSsequence, and map the second CSI-RS sequence to a time frequencylocation of a CSI-RS antenna port.

The generating unit can be configured to generate the pseudo-randomsequence and obtain the first CSI-RS sequence based on an OFDM symbol ora subframe;

the mapping unit can be configured to cut the first CSI-RS sequence toobtain the second CSI-RS sequence and map the second CSI-RS sequence tothe time frequency location of the CSI-RS antenna port in the followingway:

when the second CSI-RS sequence is mapped based on the OFDM symbol, thesecond CSI-RS sequences mapped on two OFDM symbols which are located inthe same CDM group are produced from different first CSI-RS sequences;

when the second CSI-RS sequence is mapped based on the subframe, thesecond CSI-RS sequences mapped on the two OFDM symbols which are locatedin the same CDM group are produced from different parts of same firstCSI-RS sequence.

In order to solve the above problems, the present invention furtherprovides an evolved Node B (eNB), which comprises a device forgenerating and mapping a CSI-RS sequence, and the device comprises agenerating unit and a mapping unit, wherein:

the generating unit is configured to: generate a pseudo-random sequenceaccording to a pseudo-random sequence initial value, perform a QPSKmodulation on the pseudo-random sequence, and obtain a first CSI-RSsequence according to maximum bandwidth of system;

the mapping unit is configured to: cut the first CSI-RS sequenceaccording to actual bandwidth of the system to obtain a second CSI-RSsequence, and map the second CSI-RS sequence to a time frequencylocation of a CSI-RS antenna port.

In order to solve the above problems, the present invention provides anUser Equipment (UE), which comprises a generating unit, a mappingacquiring unit, a receiving unit and a measuring unit, wherein:

the generating unit is configured to: generate a pseudo-random sequenceaccording to a pseudo-random sequence initial value, perform a QPSKmodulation on the pseudo-random sequence, and obtain a first CSI-RSsequence according to maximum bandwidth of system;

the mapping acquiring unit is configured to: cut the first CSI-RSsequence according to actual bandwidth of the system, and obtain asecond CSI-RS sequence configured to be mapped to a time frequencylocation of a CSI-RS antenna port;

the receiving unit is configured to: receive a CSI-RS sequence sent byevolved Node B (eNB) on the time frequency location of the CSI-RSantenna port;

the measuring unit is configured to: calculate the CSI-RS sequencereceived by the receiving unit and the second CSI-RS sequence obtainedby the mapping acquiring unit, and perform channel estimation andchannel measurement.

With the present invention, the CSI-RS reference signal sequence can berespectively generated or obtained at the UE terminal and eNB terminalin accordance with the stated method for generating the referencesequence and method for mapping the reference sequence according to theknown parameters, so that the calculated CSI-RS sequence can be utilizedto measure the channel at the UE terminal.

BRIEF DESCRIPTION OF DRAWINGS

FIG. 1 illustrates a sequence distribution mode when choosing the CSI-RSsequence mode FDD Normal CP based on the OFDM symbol.

FIG. 2 illustrates a sequence distribution mode when choosing the CSI-RSsequence mode TDD Only Normal CP based on the OFDM symbol.

FIG. 3 illustrates a sequence distribution mode when choosing the CSI-RSsequence mode FDD Extended CP based on the OFDM symbol.

FIG. 4 illustrates a sequence distribution mode when choosing the CSI-RSsequence mode TDD Only Extended CP based on the OFDM symbol.

FIG. 5 illustrates a sequence distribution mode when choosing the CSI-RSsequence mode FDD Normal CP based on the subframe.

FIG. 6 illustrates a sequence distribution mode when choosing the CSI-RSsequence mode TDD Only Normal CP based on subframe.

FIG. 7 illustrates a sequence distribution mode when choosing the CSI-RSsequence mode FDD Extended CP based on the subframe.

FIG. 8 illustrates a sequence distribution mode when choosing the CSI-RSsequence mode TDD Only Extended CP based on subframe.

FIG. 9 is a flow chart of the method for generating and mapping theCSI-RS sequence according to the examples of the present invention.

PREFERRED EMBODIMENTS OF THE PRESENT INVENTION

The present invention will be described in detail in combination withthe accompanying drawings and specific examples below.

As shown in FIG. 9, it is a flow chart of the method for generating andmapping the CSI-RS sequence according to the examples of the presentinvention, and the following steps are comprised.

In step 901, a pseudo-random sequence is generated according to apseudo-random sequence initial value, and a Quadrature Phase-ShiftKeying (QPSK) modulation is performed on the pseudo-random sequence, thefirst CSI-RS sequence is obtained according to the maximum bandwidth ofsystem, wherein the maximum bandwidth of system is 110 RB.

In step 902, the first CSI-RS sequence is cut according to the actualbandwidth of the system, and a second CSI-RS sequence is obtained, andthe second CSI-RS sequence is mapped to a time frequency location of aCSI-RS antenna port.

Specifically, the eNB sends the second CSI-RS sequence to UE through theabove steps;

the UE also acquires the second CSI-RS sequence of each CSI-RS antennaport through the above steps, and it performs relevant calculations onthe second CSI-RS sequence and the CSI-RS sequence received from the eNBand performs channel estimation and channel measurement.

In the method, the CSI-RS sequence can be generated and mapped based onan OFDM symbol or a subframe:

when the CSI-RS sequence is generated and mapped based on the OFDMsymbol, the second CSI-RS sequences mapped on two OFDM symbols which arelocated in the same CDM group are produced from different first CSI-RSsequences;

when the CSI-RS sequence is generated and mapped based on the subframe,the second CSI-RS sequences mapped on the two OFDM symbols which arelocated in the same CDM group are produced from different parts of thesame first CSI-RS sequence.

The examples based on the OFDM symbol and the subframe are respectivelydescribed in detail below.

Example one: the CSI-RS sequence is generated and mapped based on theOFDM symbol.

In the example, the CSI-RS sequence is generated and mapped according tothe following steps, and the mapped CSI-RS sequence is shown in FIG.1˜FIG. 4.

In step 1, the pseudo-random sequence initial value c_(init) isgenerated.

In step 2, the pseudo-random sequence c(n) is generated.

In step 3, the QPSK modulation is performed on the pseudo-randomsequence, and the first CSI-RS sequence r(m) is obtained according tothe maximum bandwidth N_(RB) ^(max,DL) of the system.

In step 4, a location index i′ is calculated according to the actualbandwidth N_(RB) ^(DL) of the system, and the first CSI-RS sequence r(m)is cut in accordance with the location index i′, and the second CSI-RSsequence r_(l,n) _(s) (i′) is obtained.

In step 5, the second CSI-RS sequence r_(l,n) _(s) (i′) is mapped to thesubcarrier k of the OFDM symbol l of the CSI-RS antenna port p, a_(k,l)^((p))=w_(l″)·r_(l,n) _(s) (i′), wherein a_(k,l) ^((p)) is a value of REcorresponding to the CSI-RS antenna port p, and w_(l″) is an orthogonalcode factor.

Wherein, the Pseudo-Random Sequence is also called a scrambling code ora scrambling code sequence, and the pseudo-random sequence initial valueis also called a scrambling code initial value.

In the step 1,

in order to fully randomize the interference between multiple cells, inone application example, the calculation of the scrambling code initialvalue adopts any one of the following formulas:c _(init)=2⁹·(7(n _(s)+1)+l+1)·(2·N _(ID) ^(cell)+1)+N _(ID) ^(cell);c _(init)=2⁹·(7(n _(s)+1)+l+1)·(2·N _(ID) ^(cell)+1);c _(init)=(7(n _(s)+1)+l+1)·(2·N _(ID) ^(cell)+1);

wherein, n_(s) is a time slot index in one radio frame, l is an OFDMindex in one time slot, and N_(ID) ^(cell) is a cell ID (a physical IDof the cell).

If the CSI-RS is considered to be used to verify the length of CP, theparameter required in calculation of such initial value can be the timeslot index, the OFDM symbol index in one time slot, the cell ID and a CPlength factor. In one application example, the calculation of thescrambling code initial value adopts any one of the following formulas:c _(init)=2¹⁰·(7·(n _(s)+1)+l+1)·(2·N _(ID) ^(cell)+1)+2·N _(ID) ^(cell)+N _(CP)c _(init)=2¹⁰·(7·(n _(s)+1)+l+1)·(2·N _(ID) ^(cell)+1)+N _(CP)c _(init)=2·(7·(n _(s)+1)+l+1)·(2·N _(ID) ^(cell)+1)+N _(CP)

wherein, n_(s) is the time slot index in one radio frame, l is the OFDMindex in one time slot, N_(ID) ^(cell) is the cell ID, and N_(CP) is theCP length factor. When the subframe is a normal CP, N_(CP)=1, otherwiseN_(CP)=0.

Furthermore, in order to make the interference of CSI-RS antenna portslocated in two adjacent subcarriers of the same cell randomized, theparameter required in calculation of such initial value can be the timeslot index, the OFDM symbol index in one time slot, the cell ID and theantenna port index related parameter. In one application example, thecalculation of the scrambling code initial value adopts any one of thefollowing formulas:c _(init)=2⁹·(7·(n _(s)+1)+l+1)·(2·N _(ID)^(cell)+1)·(2·└ANTPORT/4┘+1)+N _(ID) ^(cell)c _(init)=2⁹·(7·(n _(s)+1)+l+1)·(2·N _(ID)^(cell)+1)·(2·└ANTPORT/2┘+1)+N _(ID) ^(cell)c _(init)=(7·(n _(s)+1)+l+1)·(2·N _(ID) ^(cell)+1)·(2·└ANTPORT/4┘+1)c _(init)=(7·(n _(s)+1)+l+1)·(2·N _(ID) ^(cell)+1)·(2·└ANTPORT/2┘+1)c _(init)=4·(7·(n _(s)+1)+l+1)·(2·N _(ID) ^(cell)+1)+└ANTPORT/2┘c _(init)=2·(7·(n _(s)+1)+l+1)·(2·N _(ID) ^(cell)+1)+└ANTPORT/4┘c _(init)=2⁹·(7·(n _(s)+1)+l+1)·(2·N _(ID) ^(cell)+1)+└ANTPORT/2┘c _(init)=2⁹·(7·(n _(s)+1)+l+1)·(2·N _(ID) ^(cell)+1)+└ANTPORT/4┘c _(init)=2¹⁰·(7·(n _(s)+1)+l+1)·(2·N _(ID) ^(cell)+1)+└ANTPORT/2┘c _(init)=2¹⁰·(7·(n _(s)+1)+l+1)·(2·N _(ID) ^(cell)+1)+└ANTPORT/4┘c _(init)=2¹⁰·(7·(n _(s)+1)+l+1)·(2·N _(ID) ^(cell)+1)+└ANTPORT/2┘c _(init)=2¹⁰·(7·(n _(s)+1)+l+1)·(2·N _(ID) ^(cell)+1)+2·N _(ID) ^(cell)+└ANTPORT/4┘c _(init)=2¹¹·(7·(n _(s)+1)+l+1)·(2·N _(ID) ^(cell)+1)+4·N _(ID) ^(cell)+└ANTPORT/2┘

wherein, n_(s) is the time slot index in one radio frame, l is the OFDMindex in one time slot, and N_(ID) ^(cell) is the cell ID; ANTPORT isthe CSI-RS antenna port index related parameter and corresponds to theCSI-RS antenna port {15, 16, 17, 18, 19, 20, 21, 22}, and the value ofANTPORT can be respectively {0, 1, 2, 3, 4, 5, 6, 7}; or, the value ofANTPORT can be respectively {15, 16, 17, 18, 19, 20, 21, 22}, or, thevalue of ANTPORT is respectively {15-2, 16-2, 17-2, 18-2, 19-2, 20-2,21-2, 22-2}, or, the value of ANTPORT can be generated in accordancewith other parameters related to the CSI-RS antenna port.

Furthermore, in order to make the interference of CSI-RS antenna portslocated in two adjacent subcarriers of the same cell randomized andconsider that the CP length is verified, the parameter required incalculation of such initial value can be the time slot index, the OFDMsymbol index in one time slot, the cell ID, the antenna port indexrelated parameter and the CP length factor. In one application example,the calculation of the scrambling code initial value adopts any one ofthe following formulas:c _(init)=2¹⁰·(7·(n _(s)+1)+l+1)·(2·N _(ID)^(cell)+1)·(2·└ANTPORT/4┘+1)+2N _(ID) ^(cell) +N _(CP)c _(init)=2¹⁰·(7·(n _(s)+1)+l+1)·(2·N _(ID)^(cell)+1)·(2·└ANTPORT/2┘+1)+2N _(ID) ^(cell) +N _(CP)c _(init)=2·(7·(n _(s)+1)+l+1)·(2·N _(ID)^(cell)+1)·(2·└ANTPORT/4┘+1)+1)+N _(CP)c _(init)=8·(7·(n _(s)+1)+l+1)·(2·N _(ID) ^(cell)+1)+2·└ANTPORT/2┘+N_(CP)c _(init)=4·(7·(n _(s)+1)+l+1)·(2·N _(ID) ^(cell)+1)+2·└ANTPORT/4┘+N_(CP)c _(init)=2⁹·(7·(n _(s)+1)+l+1)·(2·N _(ID) ^(cell)+1)+2·└ANTPORT/2┘+N_(CP)c _(init)=2⁹·(7·(n _(s)+1)+l+1)·(2·N _(ID) ^(cell)+1)+2·└ANTPORT/4┘+N_(CP)c _(init)=2¹⁰·(7·(n _(s)+1)+l+1)·(2·N _(ID) ^(cell)+1)+2·└ANTPORT/4┘+N_(CP)c _(init)=2¹⁰·(7·(n _(s)+1)+l+1)·(2·N _(ID) ^(cell)+1)+2·└ANTPORT/2┘+N_(CP)

wherein: n_(s) is the time slot index in one radio frame, l is the OFDMindex in one time slot, and N_(ID) ^(cell) is the cell ID. When asubframe is a Normal CP subframe, N_(CP)=1, when the subframe is anExtended CP subframe, N_(BP)=0, and ANTPORT is the CSI-RS antenna portindex related parameter.

Furthermore, considering that the number of the CSI-RS antenna ports ofthe cell can be blindly detected, the parameter required in calculationof such initial value can be the time slot index, the OFDM symbol indexin one time slot, the cell ID, and the CSI-RS antenna port numberrelated parameter. In one application example, the calculation of thescrambling code initial value adopts any one of the following formulas:c _(init)=2⁹·(7·(n _(s)+1)+l+1)·(2·N _(ID) ^(cell)+1)·2·ANTPORTNUM+1)+N_(ID) ^(cell)c _(init)=2⁹·(7·(n _(s)+1)+l+1)·(2·N _(ID) ^(cell)+1)·2·ANTPORTNUM+1)c _(init)=2¹¹·(7·(n _(s)+1)+l+1)·(2·N _(ID) ^(cell)+1)+4N _(ID) ^(cell)+ANTPORTNUMc _(init)=2⁹·(7·(n _(s)+1)+l+1)·(2·N _(ID) ^(cell)+1)+ANTPORTNUMc _(init)=4·(7·(n _(s)+1)+l+1)·(2·N _(ID) ^(cell)+1)+ANTPORTNUMc _(init)=2⁹·(7·(n _(s)+1)+l+1)·(2·N _(ID) ^(cell)+1)·(2·ANTPORTNUM+1)+N_(ID) ^(cell)c _(init)=2¹¹·(7·(n _(s)+1)+l+1)·(2·N _(ID) ^(cell)+1)+4N _(ID) ^(cell)+ANTPORTNUM

wherein, n_(s) is the time slot index in one radio frame, l is the OFDMindex in one time slot, N_(ID) ^(cell) is the cell ID, ANTPORT is theCSI-RS antenna port index related parameter and can correspond to theCSI-RS antenna port {15, 16, 17, 18, 19, 20, 21, 22}, the value ofANTPORT is respectively {0, 1, 2, 3, 4, 5, 6, 7}; or, the value ofANTPORT is respectively {15, 16, 17, 18, 19, 20, 21, 22}, or, the valueof ANTPORT is respectively {15-2, 16-2, 17-2, 18-2, 19-2, 20-2, 21-2,22-2}; or, the value of ANTPORT can be generated in accordance withother parameters related to the CSI-RS antenna port; and ANTPORTNUM isthe CSI-RS antenna port number related parameter of one cell. Forexample: when the number of CSI-RS antenna ports is 1, the value ofANTPORTNUM is 2, when the number of CSI-RS antenna ports is 2, the valueof ANTPORTNUM is 3, when the number of CSI-RS antenna ports is 4, thevalue of ANTPORTNUM is 4, when the number of CSI-RS antenna ports is 5,the value of ANTPORTNUM is 3, or when the number of CSI-RS antenna portsis 2, the value of ANTPORTNUM is 0, when the number of CSI-RS antennaports is 4, the value of ANTPORTNUM is 1, when the number of CSI-RSantenna ports is 8, the value of ANTPORTNUM is 2, the value ofANTPORTNUM is reserved for 3, or ANTPORTNUM is other values related tothe number of the CSI-RS antenna ports of one cell.

Furthermore, considering that the number of the CSI-RS antenna ports ofthe cell can be blindly detected and the CP length can be verified, theparameter required in calculation of such initial value can be the timeslot index, the OFDM symbol index in one time slot, the cell ID, theCSI-RS antenna port number related parameter and the CP length factor.In one application example, the calculation of the scrambling codeinitial value adopts any one of the following formulas:c _(init)=2¹²·(7·(n _(s)+1)+l+1)·(2·N _(ID) ^(cell)+1)+8N _(ID)^(cell)+4N _(CP) +ANTPORTNUMc _(init)=2⁹·(7·(n _(s)+1)+l+1)·(2·N _(ID) ^(cell)+1)+4N _(CP)+ANTPORTNUMc _(init)=8·(7·(n _(s)+1)+l+1)·(2·N _(ID) ^(cell)+1)+4N _(CP)+ANTPORTNUMc _(init)=2¹²·(7·(n _(s)+1)+l+1)·(2·N _(ID) ^(cell)+1)+8N _(ID)^(cell)+2ANTPORTNUM+N _(CP)c _(init)=2⁹·(7·(n _(s)+1)+l+1)·(2·N _(ID) ^(cell)+1)+2ANTPORTNUM+N_(CP)c _(init)=8·(7·(n _(s)+1)+l+1)·(2·N _(ID) ^(cell)+1)+2ANTPORTNUM+N _(CP)

wherein, n_(s) is the time slot index in one radio frame, l is the OFDMindex in one time slot, N_(ID) ^(cell) is the cell ID, when the subframeis the Normal CP, N_(CP)=1, otherwise N_(CP)=0, ANTPORT is the CSI-RSantenna port index related parameter, and ANTPORTNUM is the CSI-RSantenna port number related parameter of the cell. For example: when thenumber of CSI-RS antenna ports is 1, the value of ANTPORTNUM is 2, whenthe number of CSI-RS antenna ports is 2, the value of ANTPORTNUM is 3,when the number of CSI-RS antenna ports is 4, the value of ANTPORTNUM is4, when the number of CSI-RS antenna ports is 8, the value of ANTPORTNUMis 5, or when the number of CSI-RS antenna ports is 2, the value ofANTPORTNUM is 0, when the number of CSI-RS antenna ports is 4, the valueof ANTPORTNUM is 1, when the number of CSI-RS antenna ports is 8, thevalue of ANTPORTNUM is 2, the value of ANTPORTNUM is reserved for 3, orANTPORTNUM is other values related to the number of the CSI-RS antennaports of one cell.

Furthermore, in order to make the interference of CSI-RS antenna portslocated in two adjacent subcarriers of the same cell randomized andconsider that the numbers of the CSI-RS antenna ports of the cell can beblindly detected, the parameter required in calculation of such initialvalue can be the time slot index, the OFDM symbol index in one timeslot, the cell ID, the CSI-RS antenna port number related parameter, theCSI-RS antenna port index related parameter and the CP length factor. Inone application example, the calculation of the scrambling code initialvalue adopts any one of the following formulas:c _(init)=2¹¹·(7·(n _(s)+1)+l+1)·(2·N _(ID)^(cell)+1)(2·└ANTPORT/4┘+1)+4N _(ID) ^(cell) +ANTPORTNUMc _(init)=2⁹·(7·(n _(s)+1)+l+1)·(2·N _(ID)^(cell)+1)(2·└ANTPORT/4┘+1)+ANTPORTNUMc _(init)=4·(7·(n _(s)+1)+l+1)·(2·N _(ID)^(cell)+1)(2·└ANTPORT/4┘+1)+ANTPORTNUMc _(init)=2¹⁰·(7·(n _(s)+1)+l+1)·(2·N _(ID)^(cell)+1)+8·└ANTPORT/4┘+ANTPORTNUMc _(init)=2¹⁰·(7·(n _(s)+1)+l+1)·(2·N _(ID)^(cell)+1)+8·└ANTPORT/2┘+ANTPORTNUM

wherein: n_(s) is the time slot index in one radio frame, l is the OFDMindex in one time slot, N_(ID) ^(cell) is the physical ID of the cell,ANTPORT is the CSI-RS antenna port index related parameter, andANTPORTNUM is the CSI-RS antenna port number related parameter of thecell. For example, when the number of the CSI-RS antenna ports is 1, thevalue of ANTPORTNUM is 2, when the number of the CSI-RS antenna ports is2, the value of ANTPORTNUM is 3, when the number of the CSI-RS antennaports is 4, the value of ANTPORTNUM is 4, when the number of the CSI-RSantenna ports is 8, the value of ANTPORTNUM is 5, or when the number ofthe CSI-RS antenna ports is 2, the value of ANTPORTNUM is 0, when thenumber of the CSI-RS antenna ports is 4, the value of ANTPORTNUM is 1,when the number of the CSI-RS antenna ports is 8, the value ofANTPORTNUM is 2, the value of ANTPORTNUM is reserved for 3, or,ANTPORTNUM is other values related to the number of the CSI-RS antennaports of one cell.

Furthermore, in order to make the interference of CSI-RS antenna portslocated in two adjacent subcarriers of the same cell randomized andconsider that the numbers of the CSI-RS antenna ports of the cell can beblindly detected and also the CP length is required to be detected, theparameter required in calculation of such initial value can be the timeslot index, the OFDM symbol index in one time slot, the cell ID, theCSI-RS antenna port number related parameter, the CSI-RS antenna portindex related parameter and the CP length factor. In one applicationexample, the calculation of the scrambling code initial value adopts anyone of the following formulas:c _(init)=2⁹·(7·(n _(s)+1)+l+1)·(2·N _(ID)^(cell)+1)(2·└ANTPORT/4┘+1)+8N _(ID) ^(cell)+4N _(CP) +ANTPORTNUMc _(init)=2⁹·(7·(n _(s)+1)+l+1)·(2·N _(ID)^(cell)+1)(2·└ANTPORT/4┘+1)+4N _(CP) +ANTPORTNUMc _(init)=2¹²·(7·(n _(s)+1)+l+1)·(2·N _(ID)^(cell)+1)(2·└ANTPORT/4┘+1)+8N _(ID) ^(cell)+2ANTPORTNUM+N _(CP)c _(init)=2⁹·(7·(n _(s)+1)+l+1)·(2·N _(ID)^(cell)+1)(2·└ANTPORT/4┘+1)+1)+2ANTPORTNUM+N _(CP)c _(init)=8·(7·(n _(s)+1)+l+1)·(2·N _(ID)^(cell)+1)(2·└ANTPORT/4┘+1)+1)+2ANTPORTNUM+N _(CP)c _(init)=2¹⁰·(7·(n _(s)+1)+l+1)·(2·N _(ID)^(cell)+1)+8·└ANTPORT/2┘+ANTPORTNUM+N _(CP)

wherein, n_(s) is the time slot index in one radio frame, l is the OFDMindex in one time slot, N_(ID) ^(cell) is the physical ID of the cell,when the subframe is the Normal CP subframe, N_(CP)=1, when the subframeis the Extended CP subframe, N_(CP)=0, ANTPORT is the CSI-RS antennaport index related parameter, and its value can be 0˜7. ANTPORTNUM isthe CSI-RS antenna port number related parameter of one cell. Forexample, when it's the CSI-RS 1 antenna port, the value of ANTPORTNUM is2, when it's the CSI-RS 2 antenna port, the value of ANTPORTNUM is 3,when it's the CSI-RS 4 antenna port, the value of ANTPORTNUM is 4, whenit's the CSI-RS 8 antenna port, the value of ANTPORTNUM is 5, or, whenit's the CSI-RS 2 antenna port, the value of ANTPORTNUM is 0, when it'sthe CSI-RS 4 antenna port, the value of ANTPORTNUM is 1, when it's theCSI-RS 8 antenna port, the value of ANTPORTNUM is 2, the value ofANTPORTNUM is reserved for 3, or ANTPORTNUM is other values related tothe number of the CSI-RS antenna ports of one cell.

In the step 2, the pseudo-random sequence c(n) is obtained in accordancewith the following ways:c(n)=(x ₁(n+N _(C))+x ₂(n+N _(C)))mod 2x ₁(n+31)=(x ₁(n+3)+x ₁(n))mod 2x ₂(n+31)=(x ₂(n+3)+x ₂(n+2)+x ₂(n+1)+x ₂(n))mod 2

wherein, x₁(0)=1, x₁(n)=0, n=1, 2, . . . , 30, N_(C)=1600,

x₂(n)=0, n=0, 1, 2, . . . , 30 are produced according to thepseudo-random sequence initial value c_(init)=Σ_(q=0) ³⁰x₂(q)·2^(q), andmod is a modular arithmetic.

In the step 3, the first CSI-RS sequence r(m) is generated in accordancewith the following ways:

${{r(m)} = {{\frac{1}{\sqrt{2}}( {1 - {2 \cdot {c( {2m} )}}} )} + {j\frac{1}{\sqrt{2}}( {1 - {2 \cdot {c( {{2m} + 1} )}}} )}}},{m = 0},1,\ldots\;,{{2N_{RB}^{\max,{DL}}} - 1}$or${{r(m)} = {{\frac{1}{\sqrt{2}}( {1 - {2 \cdot {c( {2m} )}}} )} + {j\frac{1}{\sqrt{2}}( {1 - {2 \cdot {c( {{2m} + 1} )}}} )}}},{m = \lceil {\frac{1}{2}N_{RB}^{\max,{DL}}} \rceil},\ldots\;,{\lceil {\frac{3}{2}N_{RB}^{\max,{DL}}} \rceil - 1}$

wherein, N_(RB) ^(max,DL) is the maximum bandwidth of the system, N_(RB)^(max,DL)=110.

In the steps 4˜5,

in one application example, the first CSI-RS sequence r(m) is cutaccording to

${{\mathbb{i}}^{\prime} = {{\mathbb{i}} + \frac{\lfloor {N_{RB}^{\max,{DL}} - N_{RB}^{DL}} \rfloor}{2}}},{{\mathbb{i}} = 0},1,\ldots\;,{N_{RB}^{DL} - 1}$

to obtain the second CSI-RS sequence r_(l,n) _(s) (i′) on the time slotn_(s) of the OFDM symbol l;

the second CSI-RS sequence r_(l,n) _(s) (i′) is mapped to the subcarrierk of the OFDM symbol l of the CSI-RS antenna port p, a_(k,l)^((p))=w_(l″)·r_(l,n) _(s) (i′), wherein, a_(k,l) ^((p)) is the value ofRE corresponding to the CSI-RS antenna port p, and w_(l″) is theorthogonal code factor;

wherein, N_(RB) ^(DL) is the actual system bandwidth,

$\mspace{79mu}{k = {k^{\prime} + {12{\mathbb{i}}} + \{ {{\begin{matrix}{- 0} & {{p \in \{ {15,16} \}},{{normal}\mspace{14mu}{CP}}} \\{- 6} & {{p \in \{ {17,18} \}},{{normal}\mspace{14mu}{CP}}} \\{- 1} & {{p \in \{ {19,20} \}},{{normal}\mspace{14mu}{CP}}} \\{- 7} & {{p \in \{ {21,22} \}},{{normal}\mspace{14mu}{CP}}} \\{- 0} & {{p \in \{ {15,16} \}},{{extended}\mspace{14mu}{CP}}} \\{- 3} & {{p \in \{ {17,18} \}},{{extended}\mspace{14mu}{CP}}} \\{- 6} & {{p \in \{ {19,20} \}},{{extended}\mspace{14mu}{CP}}} \\{- 9} & {{p \in \{ {21,22} \}},{{extended}\mspace{14mu}{CP}}}\end{matrix}l} = \{ {{\begin{matrix}l^{\prime} & \begin{matrix}{{when}\mspace{14mu}{using}\mspace{14mu}{the}\mspace{14mu}{extended}\mspace{14mu}{CP}\mspace{14mu}{and}\mspace{14mu}{the}\mspace{14mu}{subframe}} \\{{{structure}\mspace{14mu}{type}\mspace{14mu} 1\mspace{14mu}{or}\mspace{14mu} 2},{{the}\mspace{14mu}{first}\mspace{14mu}{symbol}\mspace{14mu}{of}\mspace{14mu}{the}\mspace{14mu}{CDM}\mspace{14mu}{group}}}\end{matrix} \\{l^{\prime} + 1} & \begin{matrix}{{when}\mspace{14mu}{using}\mspace{14mu}{the}\mspace{14mu}{extended}\mspace{14mu}{CP}\mspace{14mu}{and}\mspace{14mu}{the}\mspace{14mu}{subframe}} \\{{{structure}\mspace{14mu}{type}\mspace{14mu} 1\mspace{14mu}{or}\mspace{14mu} 2},{{the}\mspace{14mu}{second}\mspace{14mu}{symbol}\mspace{14mu}{of}\mspace{14mu}{the}\mspace{14mu}{CDM}\mspace{14mu}{group}}}\end{matrix} \\{l^{\prime} + 2} & \begin{matrix}{{when}\mspace{14mu}{using}\mspace{14mu}{the}\mspace{14mu}{normal}\mspace{14mu}{CP}\mspace{14mu}{and}\mspace{14mu}{the}\mspace{14mu}{subframe}} \\{{{structure}\mspace{14mu}{type}\mspace{14mu} 2},{{the}\mspace{14mu}{second}\mspace{14mu}{symbol}\mspace{14mu}{of}\mspace{14mu}{the}\mspace{14mu}{CDM}\mspace{14mu}{group}}}\end{matrix}\end{matrix}\mspace{79mu} l^{''}} = \{ {{\begin{matrix}{0,{l = l^{\prime}}} \\{1,{l \neq l^{\prime}},}\end{matrix}w_{i^{\prime}}} = \{ \begin{matrix}1 & {p \in \{ {15,17,19,21} \}} \\( {- 1} )^{l^{''}} & {p \in \{ {16,18,20,22} \}}\end{matrix} } } } }}$

k′ is a frequency domain location of the first CSI-RS antenna port, l′is an initial time domain location of the first CSI-RS antenna port ofthe CSI-RS, and the eNB can inform the UE of the parameter (k′,l′)through an explicit signaling; and the first CSI-RS sequence r(m) is

${{r(m)} = {{\frac{1}{\sqrt{2}}( {1 - {2 \cdot {c( {2m} )}}} )} + {j\frac{1}{\sqrt{2}}( {1 - {2 \cdot {c( {{2m} + 1} )}}} )}}},{m = 0},1,\ldots\;,{N_{RB}^{\max,{DL}} - 1}$

In another application example, the first CSI-RS sequence r(m) is cutaccording to

${i^{\prime} = {i + \frac{\lfloor {N_{RB}^{\max,{DL}} - N_{RB}^{DL}} \rfloor}{2}}},{i = 0},1,\ldots\mspace{14mu},{N_{RB}^{DL} - 1}$to obtain the second CSI-RS sequence r_(l,n) _(s) (i′) on the time slotn_(s) of the OFDM symbol l;

the second CSI-RS sequence r_(l,n) _(s) (i′) is mapped to the subcarrierk of the OFDM symbol l of the CSI-RS antenna port p, a_(k,l)^((p))=w_(l″)·r_(l,n) _(s) (i′),

wherein,

$\mspace{65mu}{k = {k^{\prime} + {12{\mathbb{i}}} + \{ {{\begin{matrix}{- 0} & {{p \in \{ {15,16} \}},{{normal}\mspace{14mu}{CP}}} \\{- 6} & {{p \in \{ {17,18} \}},{{normal}\mspace{14mu}{CP}}} \\{- 1} & {{p \in \{ {19,20} \}},{{normal}\mspace{14mu}{CP}}} \\{- 7} & {{p \in \{ {21,22} \}},{{normal}\mspace{14mu}{CP}}} \\{- 0} & {{p \in \{ {15,16} \}},{{extended}\mspace{14mu}{CP}}} \\{- 3} & {{p \in \{ {17,18} \}},{{extended}\mspace{14mu}{CP}}} \\{- 6} & {{p \in \{ {19,20} \}},{{extended}\mspace{14mu}{CP}}} \\{- 9} & {{p \in \{ {21,22} \}},{{extended}\mspace{14mu}{CP}}}\end{matrix}l} = {l^{\prime} + \{ {{{\begin{matrix}l^{''} & {{{{when}\mspace{14mu}{using}\mspace{14mu}{normal}\mspace{14mu}{CP}},{{CSI}\text{-}{RS}\mspace{14mu}{configuration}\mspace{14mu}{index}\mspace{14mu}{is}\mspace{14mu}{ 0 \sim 19}}}\mspace{14mu}} \\{2l^{''}} & {{{when}\mspace{14mu}{using}\mspace{14mu}{normal}\mspace{14mu}{CP}},{{CSI}\text{-}{RS}\mspace{14mu}{configuration}\mspace{14mu}{index}\mspace{14mu}{is}\mspace{14mu}{ 20 \sim 31}}} \\l^{''} & {{{when}\mspace{14mu}{using}\mspace{14mu}{extended}\mspace{14mu}{CP}},{{CSI}\text{-}{RS}\mspace{14mu}{configuration}\mspace{14mu}{index}\mspace{14mu}{is}\mspace{14mu}{ 0 \sim 27}}}\end{matrix}\mspace{79mu} l^{''}} \in \{ {0,1} \}},{w_{l^{''}} = \{ \begin{matrix}1 & {p \in \{ {15,17,19,21} \}} \\( {- 1} )^{l^{''}} & {{p \in \{ {16,18,20,22} \}},}\end{matrix} }} }} }}$

k′ is the frequency domain location of the first CSI-RS antenna port, l′is the initial time domain location of the first CSI-RS antenna port ofthe CSI-RS, and the eNB can inform the UE of the parameter (k′, l′)through the explicit signaling; and the first CSI-RS sequence r(m) is

${{r(m)} = {{\frac{1}{\sqrt{2}}( {1 - {2 \cdot {c( {2m} )}}} )} + {j\frac{1}{\sqrt{2}}( {1 - {2 \cdot {c( {{2m} + 1} )}}} )}}},{m = 0},1,\ldots\;,{N_{RB}^{\max,{DL}} - 1.}$

In another application example, the first CSI-RS sequence r(m) is cut toobtain the second CSI-RS sequence r_(l,n) _(s) (i′) on the time slotn_(s) of the OFDM symbol l;

the second CSI-RS sequence r_(l,n) _(s) (i′) is mapped to the subcarrierk of the OFDM symbol l of the CSI-RS antenna port p, a_(k,l)^((p))=w_(l″)=r_(l,n) _(s) (i′), wherein, a_(k,l) ^((p)) is the value ofRE corresponding to the CSI-RS antenna port p, and w_(l″) is theorthogonal code factor;

$\mspace{79mu}{{wherein},{{\mathbb{i}}^{\prime} = \{ {{{\begin{matrix}{{\mathbb{i}} + \lfloor \frac{N_{RB}^{\max,{DL}} - N_{RB}^{DL}}{2} \rfloor} & {l^{''} = 0} \\{{\mathbb{i}} - N_{RB}^{DL} + \lfloor \frac{N_{RB}^{\max,{DL}} - N_{RB}^{DL}}{2} \rfloor} & {{l^{''} = 1},}\end{matrix}\mspace{79mu}{\mathbb{i}}} = 0},1,\ldots\;,{{{2N_{RB}^{DL}} - {1\mspace{56mu} k}} = {k^{\prime} + {12( {{\mathbb{i}}\mspace{11mu}{mod}\; N_{RB}^{DL}} )} + \{ {{\begin{matrix}{- 0} & {{p \in \{ {15,16} \}},{{normal}\mspace{14mu}{CP}}} \\{- 6} & {{p \in \{ {17,18} \}},{{normal}\mspace{14mu}{CP}}} \\{- 1} & {{p \in \{ {19,20} \}},{{normal}\mspace{14mu}{CP}}} \\{- 7} & {{p \in \{ {21,22} \}},{{normal}\mspace{14mu}{CP}}} \\{- 0} & {{p \in \{ {15,16} \}},{{extended}\mspace{14mu}{CP}}} \\{- 3} & {{p \in \{ {17,18} \}},{{extended}\mspace{14mu}{CP}}} \\{- 6} & {{p \in \{ {19,20} \}},{{extended}\mspace{14mu}{CP}}} \\{- 9} & {{p \in \{ {21,22} \}},{{extended}\mspace{14mu}{CP}}}\end{matrix}l} = {l^{\prime} + \{ {{{\begin{matrix}l^{''} & {{{{when}\mspace{14mu}{using}\mspace{14mu}{normal}\mspace{14mu}{CP}},{{CSI}\text{-}{RS}\mspace{14mu}{configuration}\mspace{14mu}{index}\mspace{14mu}{is}\mspace{14mu}{ 0 \sim 19}}}\mspace{14mu}} \\{2l^{''}} & {{{when}\mspace{14mu}{using}\mspace{14mu}{normal}\mspace{14mu}{CP}},{{CSI}\text{-}{RS}\mspace{14mu}{configuration}\mspace{14mu}{index}\mspace{14mu}{is}\mspace{14mu}{ 20 \sim 31}}} \\l^{''} & {{{when}\mspace{14mu}{using}\mspace{14mu}{extended}\mspace{14mu}{CP}},{{CSI}\text{-}{RS}\mspace{14mu}{configuration}\mspace{14mu}{index}\mspace{14mu}{is}\mspace{14mu}{ 0 \sim 27}}}\end{matrix}\mspace{79mu} l^{''}} = {\lfloor {{\mathbb{i}}/N_{RB}^{DL}} \rfloor \in \{ {0,1} \}}},{w_{l^{''}} = \{ \begin{matrix}1 & {p \in \{ {15,17,19,21} \}} \\( {- 1} )^{l^{''}} & {{p \in \{ {16,18,20,22} \}},}\end{matrix} }} }} }}} }}$

k′ is the frequency domain location of the first CSI-RS antenna port, l′is the initial time domain location of the first CSI-RS antenna port ofthe CSI-RS, and the eNB can inform the UE of the parameter (k′, l′)through the explicit signaling; and the first CSI-RS sequence r(m) is

$\;{{{r(m)} = {{\frac{1}{\sqrt{2}}( {1 - {2 \cdot {c( {2m} )}}} )} + {j\frac{1}{\sqrt{2}}( {1 - {2 \cdot {c( {{2m} + 1} )}}} )}}},{m = 0},1,\ldots\;,{N_{RB}^{\max,{DL}} - 1.}}$

In another application example, the first CSI-RS sequence r(m) is cut toobtain the second CSI-RS sequence r_(l,n) _(s) (i′) on the time slotn_(s) of the OFDM symbol l;

the second CSI-RS sequence r_(l,n) _(s) (i′) is mapped to the subcarrierk of the OFDM symbol l of the CSI-RS antenna port p, a_(k,l)^((p))=w_(l″)·r_(l,n) _(s) (i′), wherein, a_(k,l) ^((p)) is the value ofRE corresponding to the CSI-RS antenna port p, and w_(l″) is theorthogonal code factor;

$\mspace{79mu}{{wherein},{i^{\prime} = \{ {\begin{matrix}{{i + N_{RB}^{\max,{DL}} - {\lfloor \frac{N_{RB}^{DL}}{2} \rfloor\mspace{14mu} l^{''}}} = 0} \\{{i - N_{RB}^{DL} + N_{RB}^{\max,{DL}} - {\lfloor \frac{N_{RB}^{DL}}{2} \rfloor\mspace{14mu} l^{''}}} = 1}\end{matrix},{i = 0},1,\ldots\mspace{14mu},{{{2N_{RB}^{DL}} - {1\mspace{79mu} k}} = {k^{\prime} + {12( {i\;{mod}\; N_{RB}^{DL}} )} + \{ {{\begin{matrix}{- 0} & {{p \in \{ {15,16} \}},{{normal}\mspace{14mu}{CP}}} \\{- 6} & {{p \in \{ {17,18} \}},{{normal}\mspace{14mu}{CP}}} \\{- 1} & {{p \in \{ {19,20} \}},{{normal}\mspace{14mu}{CP}}} \\{- 7} & {{p \in \{ {21,22} \}},{{normal}\mspace{14mu}{CP}}} \\{- 0} & {{p \in \{ {15,16} \}},{{extended}\mspace{14mu}{CP}}} \\{- 3} & {{p \in \{ {17,18} \}},{{extended}\mspace{14mu}{CP}}} \\{- 6} & {{p \in \{ {19,20} \}},{{extended}\mspace{14mu}{CP}}} \\{- 9} & {{p \in \{ {21,22} \}},{{extended}\mspace{14mu}{CP}}}\end{matrix}l} = {l^{\prime} + \{ {{{\begin{matrix}l^{''} & {{{when}\mspace{14mu}{using}\mspace{14mu}{normal}\mspace{14mu}{CP}},{{{CSI} - {{RS}\mspace{14mu}{configuration}\mspace{14mu}{index}\mspace{14mu}{is}\mspace{14mu} 0}} \sim 19}} \\{2\; l^{''}} & {{{when}\mspace{14mu}{using}\mspace{14mu}{normal}\mspace{14mu}{CP}},{{{CSI} - {{RS}\mspace{14mu}{configuration}\mspace{14mu}{index}\mspace{14mu}{is}\mspace{14mu} 20}} \sim 31}} \\l^{''} & {{{when}\mspace{14mu}{using}\mspace{14mu}{extended}\mspace{14mu}{CP}},{{{CSI} - {{RS}\mspace{14mu}{configuration}\mspace{14mu}{index}\mspace{14mu}{is}\mspace{14mu} 0}} \sim 27}}\end{matrix}l^{''}} = {\lfloor \frac{i}{N_{RB}^{DL}} \rfloor \in \{ {0,1} \}}},{w_{l^{\prime}} = \{ \begin{matrix}1 & {p \in \{ {15,17,19,21} \}} \\( {- 1} )^{l^{''}} & {{p \in \{ {16,18,20,22} \}},}\end{matrix} }} }} }}} }}$

k′ is the frequency domain location of the first CSI-RS antenna port, l′is the initial time domain location of the first CSI-RS antenna port ofthe CSI-RS, and the eNB can inform the UE of the parameter (k′,l′)through the explicit signaling; and the first CSI-RS sequence r(m) is

${{r(m)} = {{\frac{1}{\sqrt{2}}( {1 - {2 \cdot {c( {2m} )}}} )} + {j\frac{1}{\sqrt{2}}( {1 - {2 \cdot {c( {{2m} + 1} )}}} )}}},{m = \lceil {\frac{1}{2}N_{RB}^{\max,{DL}}} \rceil},\ldots\mspace{14mu},{\lceil {\frac{3}{2}N_{RB}^{\max,{DL}}} \rceil - 1}$

Example two: the CSI-RS sequence is generated and mapped based on thesubframe.

In the example, the CSI-RS sequence is generated and mapped inaccordance with the following steps, and the mapped CSI-RS sequence isshown in FIG. 5˜FIG. 8.

In step 1, a pseudo-random sequence initial value c_(init) is generated.

In step 2, a pseudo-random sequence c(n) is generated.

In step 3, a QPSK modulation is performed on the pseudo-random sequence,and the first CSI-RS sequence r(m) is obtained according to the maximumbandwidth N_(RB) ^(max,DL) of the system.

In step 4, a location index i′ is calculated according to the actualbandwidth N_(RB) ^(DL) of the system, and the first CSI-RS sequence r(m)is cut in accordance with the location index i′, and the second CSI-RSsequence r_(n) _(s) (i′) is obtained on the subframe

$\lfloor \frac{n_{s}}{2} \rfloor.$

In step 5, the second CSI-RS sequence r_(n) _(s) (i′) is mapped to thesubcarrier k of the OFDM symbol l of the CSI-RS antenna port p, a_(k,l)^((p))=w_(l″)·r_(n) _(s) (i′), wherein, a_(k,l) ^((p)) is the value ofRE corresponding to the CSI-RS antenna port p, w_(l″) is the orthogonalcode factor, and n_(s) is the time slot index.

Wherein, the pseudo-random sequence is also called a scrambling code ora scrambling code sequence, and the pseudo-random sequence initial valueis also called a scrambling code initial value.

In the step 1, in order to fully randomize interference between multiplecells, the parameter required in calculation of the initial value can bethe time slot index and the cell ID. In one application example, thecalculation of the scrambling code initial value adopts any one of thefollowing formulas:c _(init)=(└n _(s)/2┘+1)·(2N _(ID) ^(cell)+1)·2¹⁶c _(init)=(└n _(s)/2┘+1)·(2N _(ID) ^(cell)+1)c _(init)=(└n _(s)/2┘+1)·(2N _(ID) ^(cell)+1)·2¹⁶ +N _(ID) ^(cell)c _(init)=(└n _(s)/2┘+1)·(2N _(ID) ^(cell)+1)·2⁹ +N _(ID) ^(cell)

wherein, n_(s) is the time slot index in one radio frame, and N_(ID)^(cell) is the physical ID of the cell.

Furthermore, the verification of CP is considered to be performed, theparameter required in calculation of the initial value can be the timeslot index, the cell ID and the CP length factor. In one applicationexample, the calculation of the scrambling code initial value adopts anyone of the following formulas:c _(init)=(└n _(s)/2┘+1)·(2N _(ID) ^(cell)+1)·2¹⁶ +N _(ID) ^(cell) +N^(CP)c _(init)=(└n _(s)/2┘+1)·(2N _(ID) ^(cell)+1)·2¹⁶ +N _(CP)c _(init)=(└n _(s)/2┘+1)·(2N _(ID) ^(cell)+1)·(2¹⁰+2N _(ID) ^(cell) +N_(CP)

wherein: n_(s) is the time slot index in one radio frame, and N_(ID)^(cell) is the physical ID of the cell. When the subframe is the NormalCP subframe, N_(CP)=1, and when the subframe is the Extended CPsubframe, N_(CP)=0.

Furthermore, the interference reduction of the measurement betweenCSI-RS antenna ports can be considered to be performed, and in oneapplication example, the calculation of the scrambling code initialvalue adopts any one of the following formulas:c _(init)=(└n _(s)/2┘+1)·(2N _(ID) ^(cell)+1)·(2·└ANTPORT/2┘+1)·2⁹ +N_(ID) ^(cell)c _(init)=(└n _(s)/2┘+1)·(2N _(ID) ^(cell)+1)·(2·└ANTPORT/4┘+1)·2⁹ +N_(ID) ^(cell)c _(init)=(└n _(s)/2┘+1)·(2N _(ID) ^(cell)+1)·(2·└ANTPORT/2┘+1)c _(init)=(└n _(s)/2┘+1)·(2N _(ID) ^(cell)+1)·2¹⁶ +└ANTPORT/2┘c _(init)=(└n _(s)/2┘+1)·(2N _(ID) ^(cell)+1)·2¹⁶ +└ANTPORT/4┘

wherein, n_(s) is the time slot index in one radio frame, N_(ID) ^(cell)is the physical ID of the cell, ANTPORT is the CSI-RS antenna port indexrelated parameter, and its value can be 0˜7.

Furthermore, the interference reduction of the measurement betweenCSI-RS antenna ports and the verification of the CP length can beconsidered to be performed, and in one application example, thecalculation of the scrambling code initial value adopts any one of thefollowing formulas:c _(init)=(└n _(s)/2┘+1)·(2N _(ID) ^(cell)+1)·(2·└ANTPORT/2┘+1)·2¹⁰+2N_(ID) ^(cell) +N _(CP)c _(init)=(└n _(s)/2┘+1)·(2N _(ID) ^(cell)+1)·(2·└ANTPORT/4┘+1)·2¹⁰+2N_(ID) ^(cell) +N _(CP)c _(init)=(└n _(s)/2┘+1)·(2N _(ID) ^(cell)+1)·(2·└ANTPORT/4┘+1)·2+N_(CP)c _(init)=2¹⁶·(└n _(s)/2┘+1)·(2N _(ID) ^(cell)+1)·2·└ANTPORT/4┘+N _(CP)c _(init)=2¹⁶·(└n _(s)/2┘+1)·(2N _(ID) ^(cell)+1)·2·└ANTPORT/2┘+N _(CP)

wherein, n_(s) is the time slot index in one radio frame, n_(ID) ^(cell)is the physical ID of the cell, ANTPORT is the CSI-RS antenna port indexrelated parameter, and its value can be 0˜7. When the subframe is theNormal CP, N_(CP)=1, when the subframe is the Extended CP subframe,N_(CP)=0.

Furthermore, the verification of the CSI-RS antenna port is consideredto be performed, and in one application example, the calculation of thescrambling code initial value adopts any one of the following formulas:c _(init)=(└n _(s)/2┘+1)·(2N _(ID) ^(cell)+1)·(2·ANTPORTNUM+1)·2¹⁰+2N_(ID) ^(cell) +N _(CP)c _(init)=(└n _(s)/2┘+1)·(2N _(ID) ^(cell)+1)·(2·ANTPORTNUM+1)·2+N _(CP)c _(init)=(└n _(s)/2┘+1)·(2N _(ID) ^(cell)+1)·2¹²+8N _(ID) ^(cell)+4N_(CP) +ANTPORTNUMc _(init)=(└n _(s)/2┘+1)·(2N _(ID) ^(cell)+1)·2¹²+8N _(ID)^(cell)+2ANTPORTNUM+N _(CP)c _(init)=(└n _(s)/2┘+1)·(2N _(ID) ^(cell)+1)·2³+2ANTPORTNUM+N _(CP)c _(init)=(└n _(s)/2┘+1)·(2N _(ID) ^(cell)+1)·2³4N _(CP) +ANTPORTNUM

wherein, n_(s) is the time slot index in one radio frame, N_(ID) ^(cell)is the physical ID of the cell, when the subframe is the Normal CP,ANTPORTNUM is the CSI-RS antenna port number related parameter of onecell. For example, when the number of CSI-RS antenna ports is 1, thevalue of ANTPORTNUM is 2, when the number of CSI-RS antenna ports is 2,the value of ANTPORTNUM is 3, when the number of CSI-RS antenna ports is4, the value of ANTPORTNUM is 4, when the number of CSI-RS antenna portsis 8, the value of ANTPORTNUM is 5, or when the number of CSI-RS antennaports is 2, the value of ANTPORTNUM is 0, when the number of CSI-RSantenna ports is 4, the value of ANTPORTNUM is 1, when the number ofCSI-RS antenna ports is 8, the value of ANTPORTNUM is 2, the value ofANTPORTNUM is reserved for 3, or, ANTPORTNUM is other values related tothe number of CSI-RS antenna ports of one cell.

Furthermore, if only the interference reduction of the measurementbetween CSI-RS antenna ports and the verification of the CSI-RS antennaport are considered to be performed and the verification of the CP isnot considered, in one application example, the calculation of thescrambling code initial value adopts any one of the following formulas:c _(init)=(└n _(s)/2┘+1)·(2N _(ID) ^(cell)+1)·(2·ANTPORTNUM+1)·2⁹ +N_(ID) ^(cell)c _(init)=(└n _(s)/2┘+1)·(2N _(ID) ^(cell)+1)·(2·ANTPORTNUM+1)c _(init)=(└n _(s)/2┘+1)·(2N _(ID) ^(cell)+1)·2¹⁶ +ANTPORTNUMc _(init)=(└n _(s)/2┘+1)·(2N _(ID) ^(cell)+1)·4+ANTPORTNUMc _(init)=(└n _(s)/2┘+1)·(2N _(ID) ^(cell)+1)·2¹¹+4N _(ID) ^(cell)+ANTPORTNUM

wherein: n_(s) is the time slot index in one radio frame, n_(ID) ^(cell)is the physical ID of the cell, ANTPORTNUM is the CSI-RS antenna portnumber related parameter of one cell, when the number of CSI-RS antennaports is 1, the value of ANTPORTNUM is 2, when the number of CSI-RSantenna ports is 2, the value of ANTPORTNUM is 3, when the number ofCSI-RS antenna ports is 4, the value of ANTPORTNUM is 4, when the numberof CSI-RS antenna ports is 8, the value of ANTPORTNUM is 5, or when thenumber of CSI-RS antenna ports is 2, the value of ANTPORTNUM is 0, whenthe number of CSI-RS antenna ports is 4, the value of ANTPORTNUM is 1,when the number of CSI-RS antenna ports is 8, the value of ANTPORTNUM is2, the value of ANTPORTNUM is reserved for 3, or, ANTPORTNUM is othervalues related to the number of CSI-RS antenna ports of one cell.

Furthermore, in order to make the interference of CSI-RS antenna portslocated in two adjacent subcarriers of the same cell randomized andconsider that the number of CSI-RS antenna ports of the cell can beblindly detected and also the length of the CP is required to bedetected, the parameter required in calculation of such initial valuecan be the time slot index, the cell ID, the CSI-RS antenna port numberrelated parameter, the CSI-RS antenna port index related parameter andthe CP length factor. In one application example, the calculation of thescrambling code initial value adopts any one of the following formulas:c _(init)=(└n _(s)/2┘+1)·(2N _(ID) ^(cell)+1)·(2·└ANTPORT/4┘+1)·2¹¹+4N_(ID) ^(cell) +ANTPORTNUMc _(init)=(└n _(s)/2┘+1)·(2N _(ID)^(cell)+1)·(2·└ANTPORT/4┘+1)·4+ANTPORTNUMc _(init)=(└n _(s)/2┘+1)·(2N _(ID) ^(cell)+1)·(2·└ANTPORT/4┘+1)·2¹⁶+ANTPORTNUMc _(init)=(└n _(s)/2┘+1)·(2N _(ID)^(cell)+1)·2¹⁶+8·└ANTPORT/2┘++ANTPORTNUMc _(init)=(└n _(s)/2┘+1)·(2N _(ID)^(cell)+1)·2¹⁶+8·└ANTPORT/4┘++ANTPORTNUMc _(init)=(└n _(s)/2┘+1)·(2N _(ID) ^(cell)+1)·2¹⁶+2⁴·└ANTPORT/2┘+2·ANTPORTNUM+N _(CP)c _(init)=(└n _(s)/2┘+1)·(2N _(ID) ^(cell)+1)·2¹⁶+2⁴·└ANTPORT/4┘+2·ANTPORTNUM+N _(CP)c _(init)=(└n _(s)/2┘+1)·(2N _(ID)^(cell)+1)·2¹⁶+8·└ANTPORT/4┘++ANTPORTNUM

wherein, n_(s) is the time slot index in one radio frame, N_(ID) ^(cell)is the physical ID of the cell, when the subframe is the Normal CP,N_(CP)=1, when the subframe is the Extended CP subframe, N_(CP)=0,ANTPORT is the CSI-RS antenna port index related parameter, and itsvalue can be 0˜7. ANTPORTNUM is the CSI-RS antenna port number relatedparameter of one cell. For example, when the number of CSI-RS antennaports is 1, the value of ANTPORTNUM is 2, when the number of CSI-RSantenna ports is 2, the value of ANTPORTNUM is 3, when the number ofCSI-RS antenna ports is 4, the value of ANTPORTNUM is 4, when the numberof CSI-RS antenna ports is 8, the value of ANTPORTNUM is 5, or when thenumber of CSI-RS antenna ports is 2, the value of ANTPORTNUM is 0, whenthe number of CSI-RS antenna ports is 4, the value of ANTPORTNUM is 1,when the number of CSI-RS antenna ports is 8, the value of ANTPORTNUM is2, the value of ANTPORTNUM is reserved for 3, or, ANTPORTNUM is othervalues related to the number of CSI-RS antenna ports of one cell.

In the step 2, the pseudo-random sequence c(n) is generated inaccordance with the following ways:c(n)=(x ₁(n+N _(C))+x ₂(n+N _(C)))mod 2x ₁(n+31)=(x ₁(n+3)+x ₁(n))mod 2x ₂(n+31)=(x ₂(n+3)+x ₂(n+2)+x ₂(n+1)+x ₂(n))mod 2

wherein, x₁(0)=1, x₁(n)=0, n=1, 2, . . . , 30, N_(C)=1600,

x₂(n)=0, n=0, 1, 2, . . . , 30 are produced according to thepseudo-random sequence initial value c_(init)=Σ_(q=0) ³⁰x₂(q)·2^(q), andmod is a modular arithmetic.

In the step 3, the first CSI-RS sequence r(m) is generated in accordancewith the following ways:

${{r(m)} = {{\frac{1}{\sqrt{2}}( {1 - {2 \cdot {c( {2m} )}}} )} + {j\frac{1}{\sqrt{2}}( {1 - {2 \cdot {c( {{2m} + 1} )}}} )}}},{m = 0},1,\ldots\mspace{14mu},{{2N_{RB}^{\max,{DL}}} - 1}$

wherein, N_(RB) ^(max,DL) is the maximum bandwidth of the system, N_(RB)^(max,DL)=110.

In the steps 4˜5,

in one application example, the first CSI-RS sequence r(m) is cut inaccordance with i′=i+N_(RB) ^(max,DL)−N_(RB) ^(DL), i=0, 1, . . . ,2N_(RB) ^(DL)−1 to obtain the second CSI-RS sequence r_(n) _(s) (i′) onthe subframe

$\lfloor \frac{n_{s}}{2} \rfloor;$

the second CSI-RS sequence r_(n) _(s) (i′) is mapped to the subcarrier kof the OFDM symbol l of the CSI-RS antenna port p, a_(k,l)^((p))=w_(l″)·r_(n) _(s) (i′), wherein, a_(k,l) ^((p)) is the value ofRE corresponding to the CSI-RS antenna port p, and w_(l″) is theorthogonal code factor;

$\mspace{34mu}{{wherein},\mspace{79mu}{k = {k^{\prime} + {12( {i\;{mod}\; N_{RB}^{DL}} )} + \{ {{\begin{matrix}{- 0} & {{p \in \{ {15,16} \}},{{normal}\mspace{14mu}{CP}}} \\{- 6} & {{p \in \{ {17,18} \}},{{normal}\mspace{14mu}{CP}}} \\{- 1} & {{p \in \{ {19,20} \}},{{normal}\mspace{14mu}{CP}}} \\{- 7} & {{p \in \{ {21,22} \}},{{normal}\mspace{14mu}{CP}}} \\{- 0} & {{p \in \{ {15,16} \}},{{extended}\mspace{14mu}{CP}}} \\{- 3} & {{p \in \{ {17,18} \}},{{extended}\mspace{14mu}{CP}}} \\{- 6} & {{p \in \{ {19,20} \}},{{extended}\mspace{14mu}{CP}}} \\{- 9} & {{p \in \{ {21,22} \}},{{extended}\mspace{14mu}{CP}}}\end{matrix}l} = {l^{\prime} + \{ {{{\begin{matrix}l^{''} & {{{when}\mspace{14mu}{using}\mspace{14mu}{normal}\mspace{14mu}{CP}},{{{CSI} - {{RS}\mspace{14mu}{configuration}\mspace{14mu}{index}\mspace{14mu}{is}\mspace{14mu} 0}} \sim 19}} \\{2\; l^{''}} & {{{when}\mspace{14mu}{using}\mspace{14mu}{normal}\mspace{14mu}{CP}},{{{CSI} - {{RS}\mspace{14mu}{configuration}\mspace{14mu}{index}\mspace{14mu}{is}\mspace{14mu} 20}} \sim 31}} \\l^{''} & {{{when}\mspace{14mu}{using}\mspace{14mu}{extended}\mspace{14mu}{CP}},{{{CSI} - {{RS}\mspace{14mu}{configuration}\mspace{14mu}{index}\mspace{14mu}{is}\mspace{14mu} 0}} \sim 27}}\end{matrix}l^{''}} = {\lfloor \frac{i}{N_{RB}^{DL}} \rfloor \in \{ {0,1} \}}},{w_{l^{\prime}} = \{ \begin{matrix}1 & {p \in \{ {15,17,19,21} \}} \\( {- 1} )^{l^{''}} & {{p \in \{ {16,18,20,22} \}},}\end{matrix} }} }} }}}$

k′ is the frequency domain location of the first CSI-RS antenna port, l′is the initial time domain location of the first CSI-RS antenna port ofthe CSI-RS, and the eNB can inform the UE of the parameter (k′,l′)through the explicit signaling; and n_(s) is the time slot index in oneradio frame.

A device for generating and mapping the CSI-RS sequence according toexamples of the present invention comprises a generating unit and amapping unit, wherein:

the generating unit is configured to: generate a pseudo-random sequenceaccording to a pseudo-random sequence initial value, perform a QPSKmodulation on the pseudo-random sequence, and obtain a first CSI-RSsequence according to the maximum bandwidth of a system;

the mapping unit is configured to: cut the first CSI-RS sequenceaccording to the actual bandwidth of the system, obtain a second CSI-RSsequence, and map the second CSI-RS sequence to a time frequencylocation of a CSI-RS antenna port.

The device generates and maps the CSI-RS sequence based on an OFDMsymbol or a subframe, that is,

the generating unit generates the pseudo-random sequence based on theOFDM symbol or the subframe and obtains the first CSI-RS sequence;

the mapping unit maps the second CSI-RS sequence to the time frequencylocation of the CSI-RS antenna port in the following ways:

when the CSI-RS sequence is mapped based on the OFDM symbol, the secondCSI-RS sequences mapped on different OFDM symbols which are located inthe same CDM group are produced from different first CSI-RS sequences;

when the CSI-RS sequence is mapped based on the subframe, the secondCSI-RS sequences mapped on different OFDM symbols which are located inthe same CDM group are produced from different parts of the same firstCSI-RS sequence.

The specific implementation of the generating unit and mapping unit canrefer to the descriptions in example one and example two, which will notbe repeated here.

An eNB according to the examples of the present invention comprises adevice for generating and mapping CSI-RS sequence, and the devicecomprises the above generating unit and mapping unit.

A UE according to the examples of the present invention comprises agenerating unit, a mapping acquiring unit, a receiving unit and ameasuring unit, wherein:

the generating unit is configured to: generate a pseudo-random sequenceaccording to a pseudo-random sequence initial value, perform a QPSKmodulation on the pseudo-random sequence, and obtain a first CSI-RSsequence according to the maximum bandwidth of a system;

the mapping acquiring unit is configured to: cut the first CSI-RSsequence according to the actual bandwidth of the system, obtain thesecond CSI-RS sequence used to be mapped to a time frequency location ofa CSI-RS antenna port;

the receiving unit is configured to receive the CSI-RS sequence sent byan evolved Node B (eNB) in the time frequency location of the CSI-RSantenna port;

the measuring unit calculates the CSI-RS sequence received by thereceiving unit and the second CSI-RS sequence obtained by the mappingacquiring unit, and performs channel estimation and channel measurement.

The specific implementation of the generating unit and mapping acquiringunit can refer to the descriptions in example one and example two, whichwill not be repeated here.

The ordinary people skilled in the art can understand that all or partsof the steps in the above method can be completed by a programinstructing the relevant hardware, and the program can be stored in acomputer readable memory medium, such as a read-only memory, disc diskand optical disk and so on. Alternatively, all or parts of steps in theabove examples can also be implemented by using one or multipleintegrated circuits. Correspondingly, each module/unit in the aboveexamples can be implemented by using a form of hardware, and also can beimplemented by using a form of software function module. The presentinvention is not limited to any specific form of the combination ofhardware and software.

The above description is only the preferred examples of the presentinvention, which is not intended to limit the present invention, andthere are various modifications and changes in the present invention forthe skilled in the art. All the modifications, equivalent replacementsand improvements and so on made within the spirit and principle of thepresent invention shall fall into the protection scope of the presentinvention.

INDUSTRIAL APPLICABILITY

Compared with the existing technology, the CSI-RS reference signalsequence can be generated or obtained respectively at the UE terminaland eNB terminal in accordance with the stated methods for generatingand mapping the reference sequence according to the known parameters bythe present invention, so that the calculated CSI-RS sequence can beutilized to measure the channel at the UE terminal.

What is claimed is:
 1. A device for generating and mapping a ChannelState Information Reference Signal (CSI-RS) sequence, comprising agenerating unit and a mapping unit, wherein: the generating unit isconfigured to: generate a pseudo-random sequence according to apseudo-random sequence initial value, perform a Quadrature Phase-ShiftKeying (QPSK) modulation on the pseudo-random sequence, and obtain afirst CSI-RS sequence according to maximum bandwidth of system; generatethe pseudo-random sequence and obtain the first CSI-RS sequence based onan Orthogonal Frequency Division Multiplexing (OFDM) symbol or asubframe; generate the pseudo-random sequence and obtain the firstCSI-RS sequence based on the OFDM symbol; obtain the pseudo-randomsequence initial value c_(init) according to a time slot index, an OFDMsymbol index in one time slot and a cell identity (ID), or, obtain thepseudo-random sequence initial value c_(init) according to one or moreof three parameters of a CSI-RS antenna port number related parameter, aCSI-RS antenna port index related parameter and a Cyclic Prefix (CP)length factor, and the time slot index, the OFDM symbol index in onetime slot and the cell ID; the mapping unit is configured to: cut thefirst CSI-RS sequence according to an actual bandwidth of the system,obtain a second CSI-RS sequence, and map the second CSI-RS sequence to atime frequency location of a CSI-RS antenna port; cut the first CSI-RSsequence to obtain the second CSI-RS sequence and map the second CSI-RSsequence to the time frequency location of the CSI-RS antenna port in afollowing way: when the second CSI-RS sequence is mapped based on theOFDM symbol, second CSI-RS sequences mapped on two OFDM symbols whichare located in a same CDM group are produced from different first CSI-RSsequences; when the second CSI-RS sequence is mapped based on thesubframe, second CSI-RS sequences mapped on two OFDM symbols which arelocated in the same CDM group are produced from different parts of samefirst CSI-RS sequence.
 2. The device according to claim 1, wherein, thepseudo-random sequence initial value c_(init) can be one of followingvalues:c _(init)=2⁹·(7·(n _(s)+1)+l+1)·(2·N _(ID) ^(cell)+1)+N _(ID) ^(cell);c _(init)=2⁹·(7·(n _(s)+1)+l+1)·(2·N _(ID) ^(cell)+1);c _(init)=(7·(n _(s)+1)+l+1)·(2·N _(ID) ^(cell)+1);c _(init)=2¹⁰·(7·(n _(s)+1)+l+1)·(2·N _(ID) ^(cell)+1)+2·+N _(ID)^(cell) N _(CP);c _(init)=2¹⁰·(7·(n _(s)+1)+l+1)·(2·N _(ID) ^(cell)+1)+N _(CP);c _(init)=2·(7·(n _(s)+1)+l+1)·(2·N _(ID) ^(cell)+1)+N _(CP);c _(init)=2⁹·(7·(n _(s)+1)+l+1)·(2·N _(ID)^(cell)+1)·(2·└ANTPORT/4┘+1)+N _(ID) ^(cell);c _(init)=2⁹·(7·(n _(s)+1)+l+1)·(2·N _(ID)^(cell)+1)·(2·└ANTPORT/2┘+1)+N _(ID) ^(cell);c _(init)=(7·(n _(s)+1)+l+1)·(2·N _(ID) ^(cell)+1)·(2·└ANTPORT/4┘+1);c _(init)=(7·(n _(s)+1)+l+1)·(2·N _(ID) ^(cell)+1)·(2·└ANTPORT/2┘+1);c _(init)=4·(7·(n _(s)+1)+l+1)·(2·N _(ID) ^(cell)+1)+└ANTPORT/2┘;c _(init)=2·(7·(n _(s)+1)+l+1)·(2·N _(ID) ^(cell)+1)+└ANTPORT/4┘;c _(init)=2⁹·(7·(n _(s)+1)+l+1)·(2·N _(ID) ^(cell)+1)+└ANTPORT/2┘;c _(init)=2⁹·(7·(n _(s)+1)+l+1)·(2·N _(ID) ^(cell)+1)+└ANTPORT/4┘;c _(init)=2¹⁰·(7·(n _(s)+1)+l+1)·(2·N _(ID) ^(cell)+1)+└ANTPORT/2┘;c _(init)=2¹⁰·(7·(n _(s)+1)+l+1)·(2·N _(ID) ^(cell)+1)+└ANTPORT/4┘;c _(init)=2¹⁰·(7·(n _(s)+1)+l+1)·(2·N _(ID) ^(cell)+1)+└ANTPORT/2┘;c _(init)=2¹⁰·(7·(n _(s)+1)+l+1)·(2·N _(ID) ^(cell)+1)+2·N _(ID) ^(cell)+└ANTPORT/4┘;c _(init)=2¹¹·(7·(n _(s)+1)+l+1)·(2·N _(ID) ^(cell)+1)+4·N _(ID) ^(cell)+└ANTPORT/2┘;c _(init)=2¹⁰·(7·(n _(s)+1)+l+1)·(2·N _(ID)^(cell)+1)·(2·└ANTPORT/4┘+1)+2N _(ID) ^(cell) +N _(CP);c _(init)=2¹⁰·(7·(n _(s)+1)+l+1)·(2·N _(ID)^(cell)+1)·(2·└ANTPORT/2┘+1)+2N _(ID) ^(cell) +N _(CP);c _(init)=2·(7·(n _(s)+1)+l+1)·(2·N _(ID)^(cell)+1)·(2·└ANTPORT/4┘+1)+1)+N _(CP);c _(init)=8·(7·(n _(s)+1)+l+1)·(2·N _(ID) ^(cell)+1)+2·└ANTPORT/2┘+N_(CP);c _(init)=4·(7·(n _(s)+1)+l+1)·(2·N _(ID) ^(cell)+1)+2·└ANTPORT/4┘+N_(CP);c _(init)=2⁹·(7·(n _(s)+1)+l+1)·(2·N _(ID) ^(cell)+1)+2·└ANTPORT/2┘+N_(CP);c _(init)=2⁹·(7·(n _(s)+1)+l+1)·(2·N _(ID) ^(cell)+1)+2·└ANTPORT/4┘+N_(CP);c _(init)=2¹⁰·(7·(n _(s)+1)+l+1)·(2·N _(ID) ^(cell)+1)+2·└ANTPORT/4┘+N_(CP);c _(init)=2¹⁰·(7·(n _(s)+1)+l+1)·(2·N _(ID) ^(cell)+1)+2·└ANTPORT/2┘+N_(CP);c _(init)=2⁹·(7·(n _(s)+1)+l+1)·(2·N _(ID) ^(cell)+1)·2·ANTPORTNUM+1)+N_(ID) ^(cell);c _(init)=2⁹·(7·(n _(s)+1)+l+1)·(2·N _(ID) ^(cell)+1)·2·ANTPORTNUM+1);c _(init)=2¹¹·(7·(n _(s)+1)+l+1)·(2·N _(ID) ^(cell)+1)+4N _(ID) ^(cell)+ANTPORTNUM;c _(init)=2⁹·(7·(n _(s)+1)+l+1)·(2·N _(ID) ^(cell)+1)+ANTPORTNUM;c _(init)=4·(7·(n _(s)+1)+l+1)·(2·N _(ID) ^(cell)+1)+ANTPORTNUM;c _(init)=2⁹·(7·(n _(s)+1)+l+1)·(2·N _(ID) ^(cell)+1)·(2·ANTPORTNUM+1)+N_(ID) ^(cell);c _(init)=2¹¹·(7·(n _(s)+1)+l+1)·(2·N _(ID) ^(cell)+1)+4N _(ID) ^(cell)+ANTPORTNUM;c _(init)=2¹²·(7·(n _(s)+1)+l+1)·(2·N _(ID) ^(cell)+1)+8N _(ID)^(cell)+4N _(CP) +ANTPORTNUM;c _(init)=2⁹·(7·(n _(s)+1)+l+1)·(2·N _(ID) ^(cell)+1)+4N _(CP)+ANTPORTNUM;c _(init)=8·(7·(n _(s)+1)+l+1)·(2·N _(ID) ^(cell)+1)+4N _(CP)+ANTPORTNUM;c _(init)=2¹²·(7·(n _(s)+1)+l+1)·(2·N _(ID) ^(cell)+1)+8N _(ID)^(cell)+2ANTPORTNUM+N _(CP);c _(init)=2⁹·(7·(n _(s)+1)+l+1)·(2·N _(ID) ^(cell)+1)+2ANTPORTNUM+N_(CP);c _(init)=8·(7·(n _(s)+1)+l+1)·(2·N _(ID) ^(cell)+1)+2ANTPORTNUM+N_(CP);c _(init)=2¹¹·(7·(n _(s)+1)+l+1)·(2·N _(ID)^(cell)+1)(2·└ANTPORT/4┘+1)+4N _(ID) ^(cell) +ANTPORTNUM;c _(init)=2⁹·(7·(n _(s)+1)+l+1)·(2·N _(ID)^(cell)+1)(2·└ANTPORT/4┘+1)+ANTPORTNUM;c _(init)=4·(7·(n _(s)+1)+l+1)·(2·N _(ID)^(cell)+1)(2·└ANTPORT/4┘+1)+ANTPORTNUM;c _(init)=2¹⁰·(7·(n _(s)+1)+l+1)·(2·N _(ID)^(cell)+1)+8·└ANTPORT/4┘+ANTPORTNUM;c _(init)=2¹⁰·(7·(n _(s)+1)+l+1)·(2·N _(ID)^(cell)+1)+8·└ANTPORT/2┘+ANTPORTNUM;c _(init)=2⁹·(7·(n _(s)+1)+l+1)·(2·N _(ID)^(cell)+1)(2·└ANTPORT/4┘+1)+8N _(ID) ^(cell)+4N _(CP) +ANTPORTNUM;c _(init)=2⁹·(7·(n _(s)+1)+l+1)·(2·N _(ID)^(cell)+1)(2·└ANTPORT/4┘+1)+4N _(CP) +ANTPORTNUM;c _(init)=2¹²·(7·(n _(s)+1)+l+1)·(2·N _(ID)^(cell)+1)(2·└ANTPORT/4┘+1)+8N _(ID) ^(cell)+2ANTPORTNUM+N _(CP);c _(init)=2⁹·(7·(n _(s)+1)+l+1)·(2·N _(ID)^(cell)+1)(2·└ANTPORT/4┘)+1)+2ANTPORTNUM+N _(CP);c _(init)=8·(7·(n _(s)+1)+l+1)·(2·N _(ID)^(cell)+1)(2·└ANTPORT/4┘+1)+1)+2ANTPORTNUM+N _(CP);c _(init)=2¹⁰·(7·(n _(s)+1)+l+1)·(2·N _(ID)^(cell)+1)+8·└ANTPORT/2┘+ANTPORTNUM+N _(CP); wherein, n_(s) is the timeslot index in one radio frame, l is an OFDM index in one time slot,N_(ID) ^(cell) is the cell ID, and N_(CP) is the Cyclic Prefix (CP)length factor of one subframe, when the subframe is a normal CPsubframe, N_(CP)=1, when the subframe is an extended CP subframe,N_(CP)=0; ANTPORT is the CSI-RS antenna port index related parameter,and ANTPORTNUM is the CSI-RS antenna port number related parameter ofcell.
 3. A device for generating and mapping a Channel State InformationReference Signal (CSI-RS) sequence, comprising a generating unit and amapping unit, wherein: the generating unit is configured to: generate apseudo-random sequence according to a pseudo-random sequence initialvalue, perform a Quadrature Phase-Shift Keying (QPSK) modulation on thepseudo-random sequence, and obtain a first CSI-RS sequence according tomaximum bandwidth of system; generate the pseudo-random sequence andobtain the first CSI-RS sequence based on an Orthogonal FrequencyDivision Multiplexing (OFDM) symbol or a subframe; generate thepseudo-random sequence c(n) based on the OFDM symbol in accordance withfollowing ways:c(n)=(x ₁(n+N _(C))+x ₂(n+N _(C)))mod 2x ₁(n+31)=(x ₁(n+3)+x ₁(n))mod 2x ₂(n+31)=(x ₂(n+3)+x ₂(n+2)+x ₂(n+1)+x ₂(n))mod 2 wherein, x₁(0)=1,x₁(n)=0, n=1, 2, . . . , 30, N_(C)=1600, x₂(n)=0, n=0, 1, 2, . . . , 30are produced according to the pseudo-random sequence initial valuec_(init)=Σ_(q=0) ³⁰x₂(q)·2^(q), and mod is a modular arithmetic; and thefirst CSI-RS sequence r(m) based on the OFDM symbol in accordance withfollowing ways:${{r(m)} = {{\frac{1}{\sqrt{2}}( {1 - {2 \cdot {c( {2m} )}}} )} + {j\frac{1}{\sqrt{2}}( {1 - {2 \cdot {c( {{2m} + 1} )}}} )}}},{m = 0},1,\ldots\mspace{14mu},{N_{RB}^{\max,{DL}} - 1}$or${{r(m)} = {{\frac{1}{\sqrt{2}}( {1 - {2 \cdot {c( {2m} )}}} )} + {j\frac{1}{\sqrt{2}}( {1 - {2 \cdot {c( {{2m} + 1} )}}} )}}},{m = \lceil {\frac{1}{2}N_{RB}^{\max,{DL}}} \rceil},\ldots\mspace{14mu},{\lceil {\frac{3}{2}N_{RB}^{\max,{DL}}} \rceil - 1}$wherein, N_(RB) ^(max,DL) is the maximum bandwidth of the system, N_(RB)^(max,DL)=110; the mapping unit is configured to: cut the first CSI-RSsequence according to an actual bandwidth of the system, obtain a secondCSI-RS sequence, and map the second CSI-RS sequence to a time frequencylocation of a CSI-RS antenna port; cut the first CSI-RS sequence toobtain the second CSI-RS sequence and map the second CSI-RS sequence tothe time frequency location of the CSI-RS antenna port in a followingway: when the second CSI-RS sequence is mapped based on the OFDM symbol,second CSI-RS sequences mapped on two OFDM symbols which are located ina same CDM group are produced from different first CSI-RS sequences;when the second CSI-RS sequence is mapped based on the subframe, secondCSI-RS sequences mapped on two OFDM symbols which are located in thesame CDM group are produced from different parts of same first CSI-RSsequence.
 4. The device according to claim 3, wherein, the mapping unitis configured to obtain and map the second CSI-RS sequence based on theOFDM symbol in accordance with following ways: calculating a locationindex i′ according to the actual bandwidth N_(RB) ^(DL) of the systemand cutting the first CSI-RS sequence r(m) in accordance with thelocation index i′ to obtain the second CSI-RS sequence r_(l,n) _(s) (i′)of the OFDM symbol l on time slot n_(s); mapping the second CSI-RSsequence r_(l,n) _(s) (i′) to a subcarrier k of the OFDM symbol l of theCSI-RS antenna port p via a_(k,l) ^((p))=w_(l″)·r_(l,n) _(s) (i′),wherein a_(k,l) ^((p)) is a value of Resource Element (RE) correspondingto the CSI-RS antenna port p, and w_(l″) is an orthogonal code factor.5. The device according to claim 4, wherein, the location index is${i^{\prime} = {i + \frac{\lfloor {N_{RB}^{\max,{DL}} - N_{RB}^{DL}} \rfloor}{2}}},{i = 0},1,\ldots\mspace{14mu},{{N_{RB}^{DL} - 1};}$the mapping unit is configured to map the second CSI-RS sequence r_(l,n)_(s) (i′) to the subcarrier k of the OFDM symbol l of the CSI-RS antennaport p in accordance with following ways:$\mspace{79mu}{k = {k^{\prime} + {1\; 2\; i} + \{ {{\begin{matrix}{- 0} & {{p \in \{ {15,16} \}},{{normal}\mspace{14mu}{CP}}} \\{- 6} & {{p \in \{ {17,18} \}},{{normal}\mspace{14mu}{CP}}} \\{- 1} & {{p \in \{ {19,20} \}},{{normal}\mspace{14mu}{CP}}} \\{- 7} & {{p \in \{ {21,22} \}},{{normal}\mspace{14mu}{CP}}} \\{- 0} & {{p \in \{ {15,16} \}},{{extended}\mspace{14mu}{CP}}} \\{- 3} & {{p \in \{ {17,18} \}},{{extended}\mspace{14mu}{CP}}} \\{- 6} & {{p \in \{ {19,20} \}},{{extended}\mspace{14mu}{CP}}} \\{- 9} & {{p \in \{ {21,22} \}},{{extended}\mspace{14mu}{CP}},}\end{matrix}l} = {l^{\prime} + \{ {{{\begin{matrix}l^{''} & {{{when}\mspace{14mu}{using}\mspace{14mu}{normal}\mspace{14mu}{CP}},{{{CSI} - {{RS}\mspace{14mu}{configuration}\mspace{14mu}{index}\mspace{14mu}{is}\mspace{14mu} 0}} \sim 19}} \\{2\; l^{''}} & {{{when}\mspace{14mu}{using}\mspace{14mu}{normal}\mspace{14mu}{CP}},{{{CSI} - {{RS}\mspace{14mu}{configuration}\mspace{14mu}{index}\mspace{14mu}{is}\mspace{14mu} 20}} \sim 31}} \\l^{''} & {{{when}\mspace{14mu}{using}\mspace{14mu}{extended}\mspace{14mu}{CP}},{{{CSI} - {{RS}\mspace{14mu}{configuration}\mspace{14mu}{index}\mspace{14mu}{is}\mspace{14mu} 0}} \sim 27},}\end{matrix}l^{''}} \in \{ {0,1} \}},{w_{l^{\prime}} = \{ \begin{matrix}1 & {p \in \{ {15,17,19,21} \}} \\( {- 1} )^{l^{''}} & {{p \in \{ {16,18,20,22} \}},}\end{matrix} }} }} }}$ wherein, k′ is a frequencydomain location of first CSI-RS antenna port, l′ is an initial timedomain location of the first CSI-RS antenna port, and the first CSI-RSsequence r(m) is${{r(m)} = {{\frac{1}{\sqrt{2}}( {1 - {2 \cdot {c( {2m} )}}} )} + {j\frac{1}{\sqrt{2}}( {1 - {2 \cdot {c( {{2m} + 1} )}}} )}}},{m = 0},1,\ldots\mspace{14mu},{{2N_{RB}^{\max,{DL}}} - 1.}$6. An User Equipment (UE), comprising a generating unit, a mappingacquiring unit, a receiving unit and a measuring unit, wherein: thegenerating unit is configured to: generate a pseudo-random sequenceaccording to a pseudo-random sequence initial value, perform aQuadrature Phase-Shift Keying (QPSK) modulation on the pseudo-randomsequence, and obtain a first Channel State Information Reference Signal(CSI-RS) sequence according to maximum bandwidth of system; generate thepseudo-random sequence and obtain the first CSI-RS sequence based on anOrthogonal Frequency Division Multiplexing (OFDM) symbol or a subframe;the mapping acquiring unit is configured to: cut the first CSI-RSsequence according to an actual bandwidth of the system, and obtain asecond CSI-RS sequence configured to be mapped to a time frequencylocation of a CSI-RS antenna port; obtain the second CSI-RS sequenceconfigured to be mapped to the time frequency location of the CSI-RSantenna port in a following way: when the second CSI-RS sequence isobtained based on the OFDM symbol, second CSI-RS sequences mapped on twoOFDM symbols which are located in a same CDM group are produced fromdifferent first CSI-RS sequences; when the second CSI-RS sequence isobtained based on the subframe, second CSI-RS sequences mapped on twoOFDM symbols which are located in the same CDM group are produced fromdifferent parts of same first CSI-RS sequence; the receiving unit isconfigured to receive a CSI-RS sequence sent by an evolved Node B (eNB)in the time frequency location of the CSI-RS antenna port; the measuringunit is configured to calculate the CSI-RS sequence received by thereceiving unit and the second CSI-RS sequence obtained by the mappingacquiring unit, and perform a channel estimation and a channelmeasurement.
 7. The UE according to claim 6, wherein, the generatingunit is configured to generate the pseudo-random sequence and obtain thefirst CSI-RS sequence based on the OFDM symbol; the generating unit isfurther configured to: obtain the pseudo-random sequence initial valuec_(init) according to a time slot index, an OFDM symbol index in onetime slot and a cell identity (ID), or, obtain the pseudo-randomsequence initial value c_(init) according to one or more of threeparameters of a CSI-RS antenna port number related parameter, a CSI-RSantenna port index related parameter and a Cyclic Prefix (CP) lengthfactor, and the time slot index, the OFDM symbol index in one time slotand the cell ID.
 8. The UE according to claim 7, wherein, thepseudo-random sequence initial value c_(init) can be one of followingvalues:c _(init)=2⁹·(7·(n _(s)+1)+l+1)·(2·N _(ID) ^(cell)+1)+N _(ID) ^(cell);c _(init)=2⁹·(7·(n _(s)+1)+l+1)·(2·N _(ID) ^(cell)+1);c _(init)=(7·(n _(s)+1)+l+1)·(2·N _(ID) ^(cell)+1);c _(init)=2¹⁰·(7·(n _(s)+1)+l+1)·(2·N _(ID) ^(cell)+1)+2·+N _(ID)^(cell) N _(CP);c _(init)=2¹⁰·(7·(n _(s)+1)+l+1)·(2·N _(ID) ^(cell)+1)+N _(CP);c _(init)=2·(7·(n _(s)+1)+l+1)·(2·N _(ID) ^(cell)+1)+N _(CP);c _(init)=2⁹·(7·(n _(s)+1)+l+1)·(2·N _(ID)^(cell)+1)·(2·└ANTPORT/4┘+1)+N _(ID) ^(cell);c _(init)=2⁹·(7·(n _(s)+1)+l+1)·(2·N _(ID)^(cell)+1)·(2·└ANTPORT/2┘+1)+N _(ID) ^(cell);c _(init)=(7·(n _(s)+1)+l+1)·(2·N _(ID) ^(cell)+1)·(2·└ANTPORT/4┘+1);c _(init)=(7·(n _(s)+1)+l+1)·(2·N _(ID) ^(cell)+1)·(2·└ANTPORT/2┘+1);c _(init)=4·(7·(n _(s)+1)+l+1)·(2·N _(ID) ^(cell)+1)+└ANTPORT/2┘;c _(init)=2·(7·(n _(s)+1)+l+1)·(2·N _(ID) ^(cell)+1)+└ANTPORT/4┘;c _(init)=2⁹·(7·(n _(s)+1)+l+1)·(2·N _(ID) ^(cell)+1)+└ANTPORT/2┘;c _(init)=2⁹·(7·(n _(s)+1)+l+1)·(2·N _(ID) ^(cell)+1)+└ANTPORT/4┘;c _(init)=2¹⁰·(7·(n _(s)+1)+l+1)·(2·N _(ID) ^(cell)+1)+└ANTPORT/2┘;c _(init)=2¹⁰·(7·(n _(s)+1)+l+1)·(2·N _(ID) ^(cell)+1)+└ANTPORT/4┘;c _(init)=2¹⁰·(7·(n _(s)+1)+l+1)·(2·N _(ID) ^(cell)+1)+└ANTPORT/2┘;c _(init)=2¹⁰·(7·(n _(s)+1)+l+1)·(2·N _(ID) ^(cell)+1)+2·N _(ID) ^(cell)+└ANTPORT/4┘;c _(init)=2¹¹·(7·(n _(s)+1)+l+1)·(2·N _(ID) ^(cell)+1)+4·N _(ID) ^(cell)+└ANTPORT/2┘;c _(init)=2¹⁰·(7·(n _(s)+1)+l+1)·(2·N _(ID)^(cell)+1)·(2·└ANTPORT/4┘+1)+2N _(ID) ^(cell) +N _(CP);c _(init)=2¹⁰·(7·(n _(s)+1)+l+1)·(2·N _(ID)^(cell)+1)·(2·└ANTPORT/2┘+1)+2N _(ID) ^(cell) +N _(CP);c _(init)=2·(7·(n _(s)+1)+l+1)·(2·N _(ID)^(cell)+1)·(2·└ANTPORT/4┘+1)+1)+N _(CP);c _(init)=8·(7·(n _(s)+1)+l+1)·(2·N _(ID) ^(cell)+1)+2·└ANTPORT/2┘+N_(CP);c _(init)=4·(7·(n _(s)+1)+l+1)·(2·N _(ID) ^(cell)+1)+2·└ANTPORT/4┘+N_(CP);c _(init)=2⁹·(7·(n _(s)+1)+l+1)·(2·N _(ID) ^(cell)+1)+2·└ANTPORT/2┘+N_(CP);c _(init)=2⁹·(7·(n _(s)+1)+l+1)·(2·N _(ID) ^(cell)+1)+2·└ANTPORT/4┘+N_(CP);c _(init)=2¹⁰·(7·(n _(s)+1)+l+1)·(2·N _(ID) ^(cell)+1)+2·└ANTPORT/4┘+N_(CP);c _(init)=2¹⁰·(7·(n _(s)+1)+l+1)·(2·N _(ID) ^(cell)+1)+2·└ANTPORT/2┘+N_(CP);c _(init)=2⁹·(7·(n _(s)+1)+l+1)·(2·N _(ID) ^(cell)+1)·2·ANTPORTNUM+1)+N_(ID) ^(cell);c _(init)=2⁹·(7·(n _(s)+1)+l+1)·(2·N _(ID) ^(cell)+1)·2·ANTPORTNUM+1);c _(init)=2¹¹·(7·(n _(s)+1)+l+1)·(2·N _(ID) ^(cell)+1)+4N _(ID) ^(cell)+ANTPORTNUM;c _(init)=2⁹·(7·(n _(s)+1)+l+1)·(2·N _(ID) ^(cell)+1)+ANTPORTNUM;c _(init)=4·(7·(n _(s)+1)+l+1)·(2·N _(ID) ^(cell)+1)+ANTPORTNUM;c _(init)=2⁹·(7·(n _(s)+1)+l+1)·(2·N _(ID) ^(cell)+1)·(2·ANTPORTNUM+1)+N_(ID) ^(cell);c _(init)=2¹¹·(7·(n _(s)+1)+l+1)·(2·N _(ID) ^(cell)+1)+4N _(ID) ^(cell)+ANTPORTNUM;c _(init)=2¹²·(7·(n _(s)+1)+l+1)·(2·N _(ID) ^(cell)+1)+8N _(ID)^(cell)+4N _(CP) +ANTPORTNUM;c _(init)=2⁹·(7·(n _(s)+1)+l+1)·(2·N _(ID) ^(cell)+1)+4N _(CP)+ANTPORTNUM;c _(init)=8·(7·(n _(s)+1)+l+1)·(2·N _(ID) ^(cell)+1)+4N _(CP)+ANTPORTNUM;c _(init)=2¹²·(7·(n _(s)+1)+l+1)·(2·N _(ID) ^(cell)+1)+8N _(ID)^(cell)+2ANTPORTNUM+N _(CP);c _(init)=2⁹·(7·(n _(s)+1)+l+1)·(2·N _(ID) ^(cell)+1)+2ANTPORTNUM+N_(CP);c _(init)=8·(7·(n _(s)+1)+l+1)·(2·N _(ID) ^(cell)+1)+2ANTPORTNUM+N_(CP);c _(init)=2¹¹·(7·(n _(s)+1)+l+1)·(2·N _(ID)^(cell)+1)(2·└ANTPORT/4┘+1)+4N _(ID) ^(cell) +ANTPORTNUM;c _(init)=2⁹·(7·(n _(s)+1)+l+1)·(2·N _(ID)^(cell)+1)(2·└ANTPORT/4┘+1)+ANTPORTNUM;c _(init)=4·(7·(n _(s)+1)+l+1)·(2·N _(ID)^(cell)+1)(2·└ANTPORT/4┘+1)+ANTPORTNUM;c _(init)=2¹⁰·(7·(n _(s)+1)+l+1)·(2·N _(ID)^(cell)+1)+8·└ANTPORT/4┘+ANTPORTNUM;c _(init)=2¹⁰·(7·(n _(s)+1)+l+1)·(2·N _(ID)^(cell)+1)+8·└ANTPORT/2┘+ANTPORTNUM;c _(init)=2⁹·(7·(n _(s)+1)+l+1)·(2·N _(ID)^(cell)+1)(2·└ANTPORT/4┘+1)+8N _(ID) ^(cell)+4N _(CP) +ANTPORTNUM;c _(init)=2⁹·(7·(n _(s)+1)+l+1)·(2·N _(ID)^(cell)+1)(2·└ANTPORT/4┘+1)+4N _(CP) +ANTPORTNUM;c _(init)=2¹²·(7·(n _(s)+1)+l+1)·(2·N _(ID)^(cell)+1)(2·└ANTPORT/4┘+1)+8N _(ID) ^(cell)+2ANTPORTNUM+N _(CP);c _(init)=2⁹·(7·(n _(s)+1)+l+1)·(2·N _(ID)^(cell)+1)(2·└ANTPORT/4┘+1)+1)+2ANTPORTNUM+N _(CP);c _(init)=8·(7·(n _(s)+1)+l+1)·(2·N _(ID)^(cell)+1)(2·└ANTPORT/4┘+1)+1)+2ANTPORTNUM+N _(CP);c _(init)=2¹⁰·(7·(n _(s)+1)+l+1)·(2·N _(ID)^(cell)+1)+8·└ANTPORT/2┘+ANTPORTNUM+N _(CP); wherein, n_(s) is the timeslot index in one radio frame, l is an OFDM index in one time slot,N_(ID) ^(cell) is the cell ID, and N_(CP) is the Cyclic Prefix (CP)length factor of one subframe, when the subframe is a normal CPsubframe, N_(CP)=1, when the subframe is an extended CP subframe,N_(CP)=0; ANTPORT is the CSI-RS antenna port index related parameter,and ANTPORTNUM is the CSI-RS antenna port number related parameter ofcell.
 9. The UE according to claim 6, wherein the generating unit isconfigured to generate the pseudo-random sequence c(n) based on the OFDMsymbol in accordance with following ways:c(n)=(x ₁(n+N _(C))+x ₂(n+N _(C)))mod 2x ₁(n+31)=(x ₁(n+3)+x ₁(n))mod 2x ₂(n+31)=(x ₂(n+3)+x ₂(n+2)+x ₂(n+1)+x ₂(n))mod 2 wherein, x₁(0)=1,x₁(n)=0, n=1, 2, . . . , 30, N_(C)=1600, x₂(n)=0, n=0, 1, 2, . . . , 30are produced according to the pseudo-random sequence initial valuec_(init)=Σ_(q=0) ³⁰x₂(q)·2^(q), and mod is a modular arithmetic; and thegenerating unit is configured to obtain the first CSI-RS sequence r(m)based on the OFDM symbol in accordance with following ways:${{r(m)} = {{\frac{1}{\sqrt{2}}( {1 - {2 \cdot {c( {2m} )}}} )} + {j\frac{1}{\sqrt{2}}( {1 - {2 \cdot {c( {{2m} + 1} )}}} )}}},{m = 0},1,\ldots\mspace{14mu},{N_{RB}^{\max,{DL}} - 1}$or${{r(m)} = {{\frac{1}{\sqrt{2}}( {1 - {2 \cdot {c( {2m} )}}} )} + {j\frac{1}{\sqrt{2}}( {1 - {2 \cdot {c( {{2m} + 1} )}}} )}}},{m = \lceil {\frac{1}{2}N_{RB}^{\max,{DL}}} \rceil},\ldots\mspace{14mu},{\lceil {\frac{3}{2}N_{RB}^{\max,{DL}}} \rceil - 1}$wherein, N_(RB) ^(max,DL) is the maximum bandwidth of the system, N_(RB)^(max,DL)=110.
 10. The UE according to claim 9, wherein, the mappingacquiring unit is configured to obtain the second CSI-RS sequence basedon the OFDM symbol in accordance with following ways: calculating alocation index i′ according to the actual bandwidth N_(RB) ^(DL) of thesystem and cutting the first CSI-RS sequence r(m) in accordance with thelocation index i′ to obtain the second CSI-RS sequence r_(l,n) _(s) (i′)of the OFDM symbol l on time slot n_(s); the mapping acquiring unit isfurther configured to: map the second CSI-RS sequence r_(l,n) _(s) (i′)to a subcarrier k of the OFDM symbol l of the CSI-RS antenna port p viaa_(k,l) ^((p))=w_(l″)·r_(l,n) _(s) (i′), wherein a_(k,l) ^((p)) is avalue of Resource Element (RE) corresponding to the CSI-RS antenna portp, and w_(l″) is an orthogonal code factor.
 11. The UE according toclaim 10, wherein the location index is${i^{\prime} = {i + \frac{\lfloor {N_{RB}^{\max,{DL}} - N_{RB}^{DL}} \rfloor}{2}}},{i = 0},1,\ldots\mspace{14mu},{{N_{RB}^{DL} - 1};}$the mapping acquiring unit is configured to map the second CSI-RSsequence r_(l,n) _(s) (i′) to the subcarrier k of the OFDM symbol l ofthe CSI-RS antenna port p in accordance with following ways:$\mspace{79mu}{k = {k^{\prime} + {1\; 2\; i} + \{ {{\begin{matrix}{- 0} & {{p \in \{ {15,16} \}},{{normal}\mspace{14mu}{CP}}} \\{- 6} & {{p \in \{ {17,18} \}},{{normal}\mspace{14mu}{CP}}} \\{- 1} & {{p \in \{ {19,20} \}},{{normal}\mspace{14mu}{CP}}} \\{- 7} & {{p \in \{ {21,22} \}},{{normal}\mspace{14mu}{CP}}} \\{- 0} & {{p \in \{ {15,16} \}},{{extended}\mspace{14mu}{CP}}} \\{- 3} & {{p \in \{ {17,18} \}},{{extended}\mspace{14mu}{CP}}} \\{- 6} & {{p \in \{ {19,20} \}},{{extended}\mspace{14mu}{CP}}} \\{- 9} & {{p \in \{ {21,22} \}},{{extended}\mspace{14mu}{CP}},}\end{matrix}l} = {l^{\prime} + \{ {{{\begin{matrix}l^{''} & {{{when}\mspace{14mu}{using}\mspace{14mu}{normal}\mspace{14mu}{CP}},{{{CSI} - {{RS}\mspace{14mu}{configuration}\mspace{14mu}{index}\mspace{14mu}{is}\mspace{14mu} 0}} \sim 19}} \\{2\; l^{''}} & {{{when}\mspace{14mu}{using}\mspace{14mu}{normal}\mspace{14mu}{CP}},{{{CSI} - {{RS}\mspace{14mu}{configuration}\mspace{14mu}{index}\mspace{14mu}{is}\mspace{14mu} 20}} \sim 31}} \\l^{''} & {{{when}\mspace{14mu}{using}\mspace{14mu}{extended}\mspace{14mu}{CP}},{{{CSI} - {{RS}\mspace{14mu}{configuration}\mspace{14mu}{index}\mspace{14mu}{is}\mspace{14mu} 0}} \sim 27},}\end{matrix}l^{''}} \in \{ {0,1} \}},{w_{l^{\prime}} = \{ \begin{matrix}1 & {p \in \{ {15,17,19,21} \}} \\( {- 1} )^{l^{''}} & {{p \in \{ {16,18,20,22} \}},}\end{matrix} }} }} }}$ wherein, k′ is a frequencydomain location of first CSI-RS antenna port, l′ is an initial timedomain location of the first CSI-RS antenna port, and the first CSI-RSsequence r(m) is${{r(m)} = {{\frac{1}{\sqrt{2}}( {1 - {2 \cdot {c( {2m} )}}} )} + {j\frac{1}{\sqrt{2}}( {1 - {2 \cdot {c( {{2m} + 1} )}}} )}}},{m = 0},1,\ldots\mspace{14mu},{N_{RB}^{\max,{DL}} - 1.}$